Pathway to Japanese Literature

To clear her father’s tarnished name—an important mission.

“Young Mistress, please go at once to the Midorikawa family’s villa in Kamakura!”

“What’s wrong, Old Servant?”

“Nothing is wrong, but wasn’t there a promise that once summer vacation arrived, you would come stay?”

“But won’t you be inconvenienced if you’re alone, Old Servant?”

“I’m already sixty-eight—no matter what happens, I won’t be surprised.”

“Oh! Did something happen, Old Servant?”

Ayako, Dr. Tachibana's fourteen-year-old orphaned daughter, stared at Shōhei the old servant in astonishment.

“Young Mistress, then I must tell you—if you remain here, your life is in danger.”

“Such a thing… Old Servant?”

“This morning, Young Mistress’s balcony railing panel had been removed—were you aware that had you leaned on it as usual, it would have come away immediately?”

“Oh!”

“If you were to fall from that balcony, there’d be no surviving—the ground below is concrete.”

“And then—”

Shōhei brought his mouth close to Ayako’s ear. As his head—with skin like aged paper and hair turned completely white—drew near, she recalled childhood days when this old servant had carried her through botanical gardens and zoos. Before she knew it, her eyes were wet with tears of remembrance.

“Young Mistress, that’s not all. Two or three days ago—”

Shōhei whispered something to Ayako.

“Old Servant, I’m scared.”

“Therefore, please go to Kamakura at once. I’ll have your luggage sent afterward.”

“What about you, Old Servant?”

“I must keep watch here.”
“If I’m gone, there’s no telling what those villains might do.”

“But...”

“Young Mistress, do you not carry the most vital task? Should anything befall you, who in this wide world would cleanse your father’s—Dr. Tachibana’s—dreadful disgrace?”

“Old Servant, I’ll go—just don’t scold me, okay?”

“Who would scold you, Young Mistress?”
“Don’t be absurd.”

Both the old servant and Ayako were crying.
For a while, the white-haired head and the bobbed hair swayed as if nodding to each other in the shade of the terrace’s grape leaves.

The Old Servant Was Killed—Ayako’s Regret

Ayako was a maiden like a "statue of sorrow" carved by a master craftsman.

Her father Dr. Tachibana had conceived a plan to excavate the treasure vault of Hiraizumi Palace from the bottom of the Kitakami River, gathered funds from many people, and begun the work, but due to various miscalculations leading to failure, he was branded a grand swindler and died in detention before trial.

It had been last autumn—after being left utterly alone, Ayako had lived a lonely life with only the old servant Shōhei by her side, enduring persecution and insults.

At the Ushigome residence, since Dr. Tachibana’s death, hired staff no longer stayed there, startled by society’s persecution. Nevertheless, apart from Shōhei, Takiyama Tatsurō—Dr. Tachibana’s former assistant—and his wife Mieko still resided there, so Ayako’s absence caused no problems.

Ayako arrived at the Midorikawa family’s villa in Kamakura that evening.
The head of the household was a famous industrialist. His eldest son Ken'ichi was a swimmer who, though he had just turned eighteen, was already an accomplished young man with several Japanese championships to his name, while his younger sister Yōko—a school friend of Ayako’s, one year her senior at fifteen—was a girl as bright as May sunshine and as fresh as a freshly picked tomato.

The Midorikawa family—both Ken'ichi and Yōko—carefully avoided any mention of Dr. Tachibana's Hiraizumi Palace excavation, devoting themselves instead to daily enjoyment.

Swimming at Yuigahama Beach, hiking Mount Kamakura, visiting Hachiman Shrine or Shichirigahama Beach—this life of full-throated study and exercise had made Ayako immeasurably brighter in just ten days.

No wonder the Midorikawas remarked that another month of this regimen would completely transform both Ayako's health and state of mind—
Ken'ichi and Yōko moved through their days like two fairies scattering vitality and joy wherever they went.

However, an unforeseen incident occurred in an unforeseen manner.

One morning—on the veranda, while gazing at Yuigahama Beach, Ayako was absentmindedly reading the newspaper when

“Ah!”

She suddenly stood up from the rattan chair.

“Did a centipede sting you?”

Yōko rushed over.
This area had many large centipedes, and there were often big commotions when people got stung by them.

“Old Servant! Old Servant!”

“What happened to Old Servant—oh, how dreadful!”

Yōko picked up the newspaper and, upon glancing at the indicated article, also involuntarily let out a loud cry.

“Mysterious Thief Strikes Late Dr. Tachibana’s Residence”

“Old Servant Brutally Murdered; Safe Breached”

“Assistant Takiyama Under Strong Suspicion—”

Just reading these headlines made it clear this was no ordinary incident.

“I’ll go.”

After a moment, Ayako resolutely lifted her face and looked up.
After ten-odd days of rest, both her body and mind had likely regained their vigor.
In her once-pale cheeks burned a flush of excitement, and no trace remained of the lonely "statue of sorrow" that had arrived here.

“Is it safe to go to such a place, Ayako-san?”

Yōko peered worriedly into Ayako’s face.

“I was cowardly... No matter what Old Servant said, no matter how eerie things got, I should have stayed in Tokyo to look after him—he couldn’t even walk properly.”

“……”

“What will I do if those important, important records are gone?”

Ayako couldn’t wait another moment.
No sooner had she resolved to act than she was already descending the stairs and rushing out toward Hase Station like a sleepwalker.

“Ayako-san, wait for me!”
“I’ll go with you!”

After receiving permission from her mother, Yōko took her father’s car—which happened to be available—and chased after Ayako to Kamakura Station.

The Records Were Stolen—Suspicious People

“Miss, the records have been stolen.”

“What?!”

Assistant Takiyama, who had rushed out to the entrance, scratched up his palm-fiber-broom-like hair while widening his eyes in a slightly deranged manner.
From behind peered the timid eyes of his wife Mieko.

Though they knew Dr. Tachibana’s daughter was in Kamakura—being the sort who wouldn’t inform her of this commotion—they likely made a bigger fuss about the stolen records than about old servant Shōhei being killed.

“Though honestly, if the records hadn’t been stolen, I would’ve been suspected of murder—I only got cleared after proving I could open that safe freely and access the records whenever I wanted.”

“……”

Ayako and Yōko turned their backs on the assistant’s excuses and the gazes of the uniformed and plainclothes police officers, silently entering the house.

The inspection officials withdrew, and there was no one left to obstruct the two girls.

"Oh—"

Seeing the safe installed beneath the ladder steps—its top corroded by powerful chemicals, leaving a gaping hole roughly thirty centimeters square—Ayako froze in place.

“What’s wrong, Ayako-san?”

Yōko gently placed a hand on her shoulder from behind.

“If those records disappear, everything Father said will become a lie.”

“We’ll figure something out, Ayako-san. Let’s consult Brother and come up with a plan to take back the records.”

“……”

The two of them unthinkingly entered the dining room from beside the ladder steps.

“Ah!”

Inside, two police officers were securing the area, and on the floor, blood that had yet to be washed away clung like red glue.

“This is no place for young ladies to enter.”
“Go over there! Over there!”

When the officers saw the two adorable bob-haired girls enter, they tried to stop them in surprise, but by then Ayako had already rushed to the window and clung to the corpse peeking out from under the tablecloth,

“Old Servant, what happened?
“Who did such a terrible thing?”

Tears streamed down her face.

At that moment,

“Shōhei was killed?!”
“What on earth is this?!”

Someone roared in from the entrance.

“Who are you?”

Two police officers blocked the way from both sides of the door.

“Ah—my apologies, I became overexcited. I am Karasaki Sōnosuke, the one who invested half the funds into the late Dr. Tachibana’s Hiraizumi Palace excavation project.”

“Er—Karasaki Trading Company’s—”

“Indeed.”

Speaking of the president of Karasaki Trading Company—he was a fairly well-known figure in the business world.
A man of forty-five or six with slightly old-fashioned sideburns—his imposing presence made it no wonder that he somehow overwhelmed those around him.

“Ah, Mr. Karasaki!”

Assistant Takiyama rushed out.

“What about the records, Mr. Takiyama?”

“They were stolen.”

“Wh-what? Stolen? The copper plate’s gone, Dr. Tachibana’s dead, and now the records are stolen—this excavation’s finished! It’s like stamping approval on that massive fraud charge against the doctor who died before clearing his name! Fine—but how are you going to repay my losses?”

“……”

“Don’t you have copies, Mr. Takiyama?”

“There are none.”

“Not keeping copies of such vital records—that’s negligence on your part.”

“No, to reduce the risk of theft, Dr. Tachibana didn’t allow copies to be made.”

“Dr. Tachibana might’ve been fine having memorized all the records’ contents, but we’re in trouble now.”
“In any case, you must ask the police and have them search for it by any means necessary.”
“Depending on how things go, we could even offer a reward—say, around ten thousand yen.”

Karasaki Sōnosuke left through the entrance without even looking at the safe or the old servant.

“Ayako-san, don’t you think that person is acting strange?”

“Huh?”

After seeing off Karasaki Sōnosuke, Yōko whispered something strange into Ayako’s ear.

"He’s always coming to this house, isn’t he?"

"Huh? He just... comes in whenever he wants?"

"If he’s so close to the household, why did he leave without stepping inside? Why didn’t he say a single word to you, Ayako-san? And why wouldn’t he check the safe after such important records were stolen—isn’t that odd?"

“……”
“And then, won’t you ask Mr. Takiyama where he was last night when the Old Servant was killed? Whether his wife was with him—and another thing—could you see the clothes Mr. Takiyama was wearing last night?”
Yōko began saying strange things.

Buried at the Riverbed—The Ruins of the Hiraizumi Civilization

Ayako and Yōko returned to the Midorikawa family’s villa in Kamakura that same day.

“Brother, something terrible has happened!”

“I heard about it—it’s regarding the Old Servant at your house, right?”

Ken’ichi, who had returned from swimming practice, came out to the veranda in a hurry, his splendid sun-bronzed physique hastily draped in a yukata.

“That’s part of it, but it’s something much worse.”
“I think I should have you hear from me about Father—Dr. Tachibana—and his work...the excavation of Hiraizumi Palace in detail.”

“Things have taken a bad turn, haven’t they?”

Ken’ichi, Yōko, and Ayako, cooled by the breeze sweeping across the ivy-clad veranda, pulled their rattan chairs close together.

“You already know this—Father, Dr. Tachibana—was called a fraudster, a thief, and died while detained awaiting trial, but he would never do such things. That was due to bad luck and being deceived by some unknown villain.”

“……”

Ayako began to speak anxiously.

The story went like this.—Ayako’s father, Dr. Tachibana, was a renowned historian who, while investigating the historical sites of Hiraizumi with particular interest, ended up making a tremendous discovery.

This is detailed in Japanese history books: Fujiwara no Kiyohira, the Chinjufu Shogun, relocated from Toyoda-no-Tate in Oshu to Hiraizumi, where he built a palace during the reign of Emperor Horikawa—approximately 840 years ago. For four generations—Kiyohira, Motohira, Hidehira, and Yasuhira—they resided in Hiraizumi Palace and commanded the entirety of Oshu.

During that time, there were wars and visits from Ushiwakamaru to Hidehira among various events, but in any case, Hiraizumi once prospered no less than Kamakura—there were times when even Kiyomori or Yoritomo could do nothing about the Fujiwara family's influence.

Beyond Hiraizumi Palace—also called Oku Imperial Palace—stood grand structures including the Willow Imperial Palace built by Kiyohira, the Temple Complex Imperial Palace where Hidehira resided, and Takadachi Palace where Yoshitsune took refuge after being pursued by Yoritomo. Outside these, retainers' residences stood in rows. To the west lay Chūson-ji Temple and Konjikidō (which still remains today), while to the south rose massive temples like Mōtsū-ji—a prosperity beyond modern imagination, with ten grand temple halls and a thousand monastic quarters. Yet by sheltering Yoshitsune, they provoked Yoritomo's wrath. In Bunji 5 (1189—745 years ago), they confronted his armies, were defeated in battle, and nearly everything was reduced to ashes in the flames of war.

This much is the surface-level history anyone knows, but according to Dr. Tachibana’s research, Fujiwara no Hidehira—a peerless hero of his generation—had allegedly buried an immense trove of gold and silver treasures, along with ancient artworks, beneath Hiraizumi Palace for his descendants’ sake.

However, afterward, the Kitakami River, which had been flowing east of Hiraizumi, altered its course, diverting westward to flow over Hiraizumi Palace, the Willow Imperial Palace, the Temple Complex Imperial Palace, and part of Takadachi Palace—the most crucial sites of the Fujiwara clan’s four-generation splendor—submerging the majority of these ancient ruins beneath its waters.
This is absolutely not a fabrication.
The details become clear when comparing Hiraizumi’s old maps with current ones.

Dr. Tachibana was not a man concerned with greed or personal gain, but he pushed forward diligently with his excavation plan in the hope that if they could open the great underwater vault—believed to lie submerged in Nekoma-ga-fuchi, south of Takadachi Palace (also called Hangan Palace)—they might obtain historically invaluable reference materials. Yet, plagued by the scholar’s lament—insufficient funds to sustain his work—he ultimately decided to discuss the matter with an acquaintance: the industrialist Karasaki Sōnosuke.

Oshu was a famous gold-producing region, and the Fujiwara family, who held Kinkasan as their territory, had wealth beyond imagination.

Upon hearing that the secret chamber of Hiraizumi Palace likely contained mountains of gold dust, stretched gold bars, sea cucumber-shaped ingots, and gold bullion hidden within, Karasaki Sōnosuke became ambitious.
He promptly contributed a portion of the capital himself, collected additional funds widely from the public, and finally commenced the work in the spring of last year.

Fortunately, Dr. Tachibana—being a historian—obtained ancient records of Hiraizumi and, as he advanced his work using them, excavated a single thin copper plate from the ruins of the former Willow Imperial Palace.
As a result of the appraisal, it was determined that Hidehira had ordered craftsmen to engrave the treasure vault’s location onto it. Though most had corroded, to someone knowledgeable, it remained a sufficiently useful map.

Up to this point, the Hiraizumi Palace excavation had proceeded smoothly. However, in autumn of last year, a diver died due to some mishap while searching the bottom of Nekoma-ga-fuchi, and at the same time, the painstakingly obtained copper plate map was lost, causing the excavation project to completely collapse.

The investors—incited by whom—suddenly began raising an uproar.
Around that time, as public attention focused intensely on salvaging gold coins from a sunken ship, the Hiraizumi Palace excavation also faced fraud charges. Its representative, Dr. Tachibana—with no means to establish his innocence—suddenly died of heart failure.

Ayako, left behind, understood nothing.
Assistant Takiyama continued performing only superficial work while safeguarding the records, but society at large dismissed him as a fraudster and refused to engage with him any longer.

The Suspicious Takiyama: The Mystery of the Movie Program

“Father would never do such things.”
“There must be some big mistake.”
“There were even people who said the diver was killed because he was mistaken for Father—”

Ayako concluded her account.
There were many things she wanted to say, but Ayako, having just turned fourteen, could not grasp anything beyond this.

Yet in her large, resolute eyes and firmly set, lovely lips, one could clearly see she had bravely resolved to stake her life on clearing Father’s tarnished name and avenging the loyal Old Servant.

“Brother, what do you think? I’m certain villains are behind all sorts of tampering—Mr. Karasaki’s behavior was also suspicious.”

Yōko interjected.

“Old Servant often said—‘Mr. Karasaki was supposed to have no involvement anymore! Because Father couldn’t endure how profit-driven they were running his scholarly work—he forced himself to repay Mr. Karasaki’s share and even took back the receipt.’”

“Well...”

Ayako remembered something crucial.

“Moreover, the Old Servant still seemed to know all sorts of things.”
“At times he looked like he wanted to speak—‘Brr! If I say this, my life’ll be in danger,’ he’d say, shaking his head like it was a joke.”

Ken’ichi and Yōko felt as though they’d come face-to-face with something dreadful.

“Everything about him reeks of suspicion—Brother! Last night Mr. Takiyama said he went to the movies with his wife—but there were two copies of the same theater’s program in his pocket!”

Even Yōko was saying strange things.

“Did you investigate such details? Probably for him and his wife,” said Ken’ichi.

“But there was also one copy of the same program tucked into his wife’s handbag. Having three copies for two people is strange, don’t you think?”

“There must have been someone else with them.”

“I checked that too.”
“Then Mr. Takiyama made a strange face and insisted they were definitely alone.”
“And he said he didn’t meet anyone on the way there, on the way back, or even at the movie theater.”

“...”

“And then, how do you explain that Mr. Takiyama’s suit sleeve was slightly burned by a strong acid?”

What Yōko was saying grew increasingly mysterious.

“Yōko-chan suspects Takiyama, doesn’t she? —The police probably suspected him too at first but figured there was no reason to doubt someone who had the safe key and could open it freely—so they let him go.”

“It seems so.”
“But—something’s off.”

The three exchanged glances in the evening gloom.

“Who’s there?!”

Suddenly, Ken'ichi stood up.

A figure thudded across the lawn as they fled.

"We can't speak carelessly."
"We're being watched."

Ken’ichi urged his sister and Ayako to enter his second-floor room.

The grand stage of action—to Hiraizumi, to Hiraizumi!!

“Yōko-chan, could you tell me about the three programs one more time?”
“Does that mean Assistant Takiyama took someone else besides his wife to the movie theater?”

Ken’ichi asked again.
He knew that his sister Yōko’s mind was terrifyingly sharp, possessing an intuitive power that no adult could match.

“Either he’s hiding that there was a companion, or else—I think Mr. Takiyama entered the movie theater with his wife, left her inside, went out alone to do something, then returned to the theater again and went home together with her.”

“Hmm, how does that work?” said Ken’ichi.

“At movie theaters, when you buy a ticket and enter, they always give you a program at the entrance right? If we assume Mr. Takiyama entered the movie theater twice, then having three programs for two people stops being strange.”

“Interesting—so you’re saying Mr. Takiyama left the movie theater alone midway, quietly returned to Ushigome, killed Old Servant, and broke into the safe?”

“I wouldn’t phrase it that way, you know. But it’s not impossible. The movie theater’s right nearby in Kagurazaka.”

For a while, Ken’ichi could only marvel at the uncanny workings of Yōko’s mind.

“But at the movie theater entrance, they might’ve accidentally handed out two programs together,” said Ken’ichi.

“That could happen, you know.”
“But the ones in Mr. Takiyama’s pocket were each folded in half separately, you know.”

“What if someone received two copies at once, read just one, and then stuffed them in separately?”
“That’s not the case, you know. The program on top has pages that aren’t torn at all, you know.”

“...”

Ken’ichi had completely surrendered.
But that alone still wasn’t enough to make Takiyama a murderer.

“Did you tell the police about that?”

“I can’t say such a thing, you know. But if Mr. Takiyama did something bad, he might confess, you know.—And besides, the acid on his suit sleeve is quite suspicious, don’t you think?”

Yōko’s suspicions were deeply rooted.

“Moreover,” said Ken’ichi, “there might be an excuse that he returned from the movie theater and—startled to find the safe destroyed—panicked and stuck his hand through the hole on top.”

“Oh, Brother, you sound just like a lawyer!”

“Yōko-chan’s the prosecutor here, aren’t you?”
“Ha ha ha ha!”

“But that’s just an excuse,” said Yōko. “I think it’s only natural he’d be suspected under the circumstances. Since Mr. Takiyama has the key to the safe, he could’ve simply opened the door to look inside without sticking his hand through that hole on top, couldn’t he?”

“But the Hiraizumi Palace records inside are something Takiyama can access anytime,” countered Ken’ichi. “There’s no need for him to kill Old Servant just to get them, right?”

Ken’ichi also played his last trump card.

“Probably, the Hiraizumi Palace records were important at first, but now they’re no longer a secret or anything—Mr. Takiyama and that man named Karasaki can freely access them too, right?”

Yōko proposed another new theory.

“...”

“So those records don’t matter at all—isn’t the missing copper plate actually what’s important? Since losing the copper plate was enough to ruin the excavation—”

“...”

“To avoid being suspected of killing Old Servant Shōhei,” said Ayako quietly but pointedly. he deliberately broke into the safe and either hid or burned those less important records—”

What brilliance! Both Ken’ichi and Ayako found themselves astonished once more by Yōko’s formidable intellect.

“Then let’s go check—if we search Miss Ayako’s house in Ushigome again—”

“No good,” Brother—there was a lot of ash from burned Japanese paper in the Chōshū-style stove.”
“I thought I could even see traces of binding holes left intact,” she added with hesitant conviction. “but I kept quiet because I didn’t know if detectives would believe me.”

The two of them had to marvel once more.
It was impossible to tell just how far Yōko’s perceptiveness reached.

“So, Yōko-chan—do you think Takiyama killed Old Servant?” said Ken’ichi.

“Such a thing isn’t clear, you know. Isn’t it possible that someone is trying to make people suspect Mr. Takiyama? That man Karasaki is quite suspicious too—after all, he wanted Old Servant out of the way.”

“Well then, what should we do now, Yōko-chan?”

In swimming, he was hailed as a great athlete—“the pride of Japan”—but when it came to matters of intellect like this, even young Ken’ichi was utterly outmatched by his younger sister.

“The missing records aren’t that important, and if it’s unlikely we’ll figure out who killed Old Servant anytime soon, wouldn’t it be better to just go ahead and go to Hiraizumi? Well, Brother, do you have about a week free?”

“I do—practice just finished, and I was thinking of going to the Japanese Alps or somewhere. Let’s go to Hiraizumi.”
“Yōko-chan, Ayako-san too.”

The adventure-loving Ken’ichi became utterly ecstatic.

“Let’s do that. Searching for that copper plate and investigating the murdered diver—wouldn’t it be more exciting to find Hiraizumi Palace’s treasure vault with our own hands? Though there might be some pretty dangerous things involved—”

“A little danger is everywhere, you know.”
“First off, once we discover the treasure vault of Hiraizumi Palace, Ayako’s father’s disgrace will be vindicated.”

“Let’s go, Ayako-san.”

When Yōko took her hand, Ayako found herself shedding tears before she knew it.

In her silently upturned eyes shone a light of admiration for Yōko’s wisdom and Ken’ichi’s chivalry.

To Hiraizumi— To Hiraizumi— What in the world awaited these three youths there?

Yōko Wrote: “A Little Comedy in the Corridor”

“Ayako-san, don’t you know that person?”

“I don’t know, why do you ask?”

Yōko stood before the washstand and pointed through the half-open door at the dapper young man in the second-class carriage. His head resembled a dragonfly’s compound eyes, with a red tie, boldly striped suit, elongated jaw, and pallid complexion—what an utterly disagreeable visage!

Ken’ichi—wearing his stand-collar school uniform in the same carriage, his sun-browned face radiating open-hearted cheer—appeared by contrast like a youth from an entirely different species when measured against this man.

“What about him, Yōko-san?”

“There’s something strange—someone’s been peeking into your bag and checking your handbag.”

“Oh!”

“Brother is so oblivious—he doesn’t notice such things at all. The moment someone starts talking about swimming, he gets completely absorbed.”

“What should we do? I’m scared—I am.”

“It’s okay, leave it to me—we must be nearing Sendai.”

“Yes.”

The train soon arrived at Sendai Station.
The stop lasted ten minutes, and for a while, the platform bustled with vendors' calls and passengers boarding and alighting, but when the departure bell rang, the passengers who had been on the platform scrambled to return to the train cars.

“Come on, let’s get off, Brother.”

Yōko suddenly took down the luggage from the overhead rack.

“Hiraizumi isn’t here yet, Yōko-chan.”

“But we were supposed to get off here to take care of a very, very important secret matter—Brother has forgotten all about it, hasn’t he? Right, Ayako-san?”

“…………”

“Wait, wait! You two can’t just go getting off on your own!”

Ken’ichi, in a frantic rush, grabbed suitcases in both hands and leaped off the second-class car that had just started moving.

"Oh?"

The flustered modern-dressed young man left behind was a comical sight.
He too hurriedly gathered his nearby luggage, plopped his hat askew on his head, dangled his shoes by their laces, and clutched his briefcase—

"Danger! Don’t jump off!"

Ignoring the conductor’s attempts to stop him, he leaped from the moving train onto the platform.

Landing hard on his rear, he picked up his fallen hat and headed toward the ticket gate—but Ayako, Yōko, and Ken’ichi’s group, who had just disembarked moments before, were nowhere to be seen.

“Oh?”

The flustered young man turned around just to be sure—and lo and behold, from the window of the third-class compartment next to the one they had been riding in on the now-departing train, three overlapping heads were watching this way.

“Farewell.”

The mischievous Yōko wiggled her finger under her nose.
Even Ayako—the “statue of sorrow”—could no longer contain herself and burst into laughter.
Only honest Ken’ichi, who had been dragged off the second-class car and made to board the adjacent third-class compartment, still seemed unable to grasp why this had happened and watched the little platform comedy with a completely puzzled look.

“I wonder if it’s all right to do such a thing, Yōko-san. It seems rather pitiable, doesn’t it?” said Ayako.

“But getting off was their own choice! I just found it so funny—so funny—”

Yōko was rolling with laughter.

Continuing Dr. Tachibana's—the great undertaking he had left behind—

“Oh, Young Mistress!”

“Mr. Hanai, have you seen the telegram?”

“Oh, I’ve completely tidied up the cabin along with the diver’s wife.”

Hanai Ichirō, the student assistant, received the bag from Ayako and placed it into the hired car.

“Can three people stay here?”

“Up until last year, seven people stayed here.”

Having been trusted by Dr. Tachibana and entrusted with managing Hiraizumi Palace’s excavation office, Hanai Ichirō was a surprisingly reliable man for his age.

“Has anything unusual happened?”

“Nothing at all.”
“The Kitakami River embankments remain untouched, and the Copper Plate Map’s location is still unknown—so O-Taka-san and I have just been waiting here until work resumes. As for me, I wouldn’t be surprised if I had to stay here forever.”
“Bored? How could I be? There’s no better place for study than this.”

Hanai said such things.
For Hanai, who said he intended to take the professional certification exam next year or so, there could have been no better place to study than this.

Soon, the group arrived at the excavation office cabin—built nestled among the trees under Hangan Palace as if playing hide-and-seek.

"Oh my, oh my, Young Mistress."

The middle-aged woman who welcomed them with these words was the spouse of the diver who had died last year at Nekoma-ga-fuchi—a woman named O-Taka-san, dressed in a white apron with her hair pulled taut into a bun, giving her an unexpectedly metropolitan air.

The cabin had two wooden-floored rooms each about six tatami mats in size, along with a small storage room—it was inconvenient if one insisted on calling it so, but for just ten or twenty days in summer, treating it as camping, five or seven people could manage to live there.

“Oh my, it must have been quite a task—the riverbed is so visible now.”

Exiting the cabin and descending to the banks of the Kitakami River, she could truly grasp the hardships her father, Dr. Tachibana, had endured over the past year or two. To uncover the secrets of the ancient Hiraizumi Palace, they had built a massive embankment on the Kitakami River to divert its flow into the old Sakura River basin, and were now excavating the dried riverbed in every direction.

“Ayako-san’s father started an incredible task, didn’t he?”

Ken’ichi, upon seeing the remains of this colossal construction project, couldn’t help but click his tongue in amazement.

“But since Mr. Hanai and the others have kept watch and prevented anyone from disturbing the site, we can resume work right away! And since my father will cover the costs, let’s quickly gather workers and start the excavation.—Mr. Hanai can oversee things, can’t he?”

Yōko, as ever, put her sharp mind to work and pushed things forward vigorously.
If Ken’ichi and Yōko’s father—the tycoon Mr. Midorikawa—supported us, this project would progress more smoothly than expected.

“I intend to manage it.
I’ve mostly been the one handling things up until now anyway.”

“That worked out just perfectly, didn’t it?”

Ayako also seemed truly happy that they could continue her father Dr. Tachibana’s work.

Hanai was stabbed—in Ken'ichi’s place.

Laborers were suddenly gathered, the embankments were newly extended, and the excavation project of Hiraizumi Palace was resumed.

The one commanding the many workers was Hanai Ichirō, the student assistant; handling all meal preparations was O-Taka-san.

Ken’ichi was merely a supervisor in title; whenever he had a spare moment, he would dive into the depths of the Kitakami River to swim or search the rapids for ayu, eels, and haya, making him utterly unreliable in his role.

Between Aoba Mountain and waters like pooled jade, how greatly the sight of two utterly adorable girls—Ayako and Yōko—flitting about must have comforted the eyes and hearts of the workers.
Both wore light Western-style dresses in white and pink; one flitted about like a butterfly, while the other moved as quietly as a lily, observing the challenging excavation project.

“That Mr. High-collar we shook off in Sendai has been here—for three whole days already—”

One day, Yōko whispered softly to Ayako.

“Oh my!”

Yōko burst into laughter as though she couldn’t help herself, but Ayako, ever the worrier, shuddered at an ominous premonition.

That evening, Hanai Ichirō felt slightly unwell and was looking pale.
It was probably because he had been exposed to the sun all day while shouting orders to the workers.

“It’s not right for you to sleep in the storage room.”
“That place has small windows, and leaving the door open makes it unsafe.”

Ken’ichi said such things.

“It’s okay—I’m used to it.”

“No—if you get sick, it’ll be a real problem.”
“I may be called the supervisor, but it’s just in name.”

Ken'ichi forcibly had Hanai Ichirō lie down on his own six-tatami bed and went to the straw mat in the storage room himself.

It was that night.

“Don’t you think something’s off, Yōko-san?”

In the middle of the night, Ayako shook Yōko, who was sleeping beside her, awake.

“Why? Ayako-san?”

“It sounds like something’s groaning.”

“I suppose so.”

The two of them stepped down from the bed in their nightclothes, took a handheld lantern, and headed toward the neighboring room.
The groaning sound was coming from there.

“Mr. Hanai!”

In Brother Ken'ichi’s bed—only tonight—Hanai was supposed to be sleeping.

“Something’s off—could Mr. Hanai’s illness have taken a turn for the worse?”

The two of them exchanged glances, then resolutely pushed open the door.
Illuminated by two handheld lanterns,

“Ah!”

The floor lay drenched in blood, with Hanai Ichirō collapsed upon it.

The commotion erupted instantly.
Ken'ichi, O-Taka-san, and the labor boss came rushing over.

When they lifted him, they found Hanai barely breathing—his shoulders and hands savagely wounded.
They made calls, sent runners for help, and summoned the village doctor—the hut seethed like a boiling cauldron—but by dawn’s light, they’d rushed him to Ichinoseki Hospital by car. Hearing “He’ll keep his life at least,” they finally managed to breathe again.

If Hanai were gone, the excavation work would hit a dead end, but at this point, they couldn’t afford to halt it. Since O-Taka-san had gone to Ichinoseki as Hanai’s attendant, overseeing meals fell to Ayako, and Ken’ichi had no choice but to take over directing the laborers Hanai had been managing.

“It would’ve been better if I’d been the one attacked instead of Hanai,” he said. “This is tough.”

Ken’ichi, unaccustomed to the work, was thoroughly overwhelmed.

“But Brother was thought to be the leader, you know. Because the villain didn’t realize the bedroom had been changed that night and came intending to stab you, Brother.”

Yōko, as ever, saw straight through to the very heart of things.

A horizontal hole in the river—could it be the entrance to the treasure vault?

“This is a problem. The laborers have all withdrawn.”

“Huh?!”

“The riverbank’s completely deserted.”

“What’s wrong, Brother?”

“Someone’s been poisoning the laborers’ minds.—Don’t let Ayako-san hear about this.”

“What kind of things, Brother?”

Ken'ichi and Yōko stood beneath the tree-shaded darkness and midsummer sun’s glare, whispering as they stared at the riverbed exposing its parched skin.

“Dr. Tachibana was a con artist who died in prison. If you stick your neck into this kind of job, you might get your daily wages, but on the flip side, you never know when the cops might come and haul everyone away—that’s what someone’s been saying. Because more than half of the laborers are honest locals—they got scared and withdrew, you know. Even if we say we’ll double the wages, it’s no use.”

“Brother.”

“I’ve had enough!”

“Brother, that won’t do! We’ll send a telegram to Tokyo and call a hundred laborers!”

“Can we really do that?”

“We absolutely can! They’ll arrive in less than three days. Doesn’t everyone say Tokyo’s drowning in unemployed workers anyway?”

Yōko said something outrageous.
Even the great athlete who was called Japan's pride could never match his younger sister in intelligence.

“What’s wrong?”
“Why are there no laborers at all?”

Before long, Ayako had noticed too, but Yōko—explaining they’d decided to summon laborers from Tokyo—spoke with deliberate vagueness and succeeded in placating her.

“But waiting around like this is ridiculous,”
“When you’ve worked seriously even two or three days, staying still feels like asking for divine punishment.”

Ken'ichi strolled off to the riverbank, but after about thirty minutes, he came flying back drenched in sweat.

“T-This is bad!”

“What’s wrong, Brother?”

“W-water… a glass!”

Ayako drew and offered a glass of water, and he gulped it down in one breath,

“At the cliff of the riverbed where Takadate’s ruins stood, there was a horizontal hole like a rat’s burrow. Just to be safe, when I struck it two or three times with a pickaxe, a large hole opened with a poof.”

“Huh?!”

“When I peeked inside, it was a splendid tunnel.”
“The inside was piled up with stones.”
“Since I thought it might be the entrance to the treasure vault, I hurriedly blocked the hole and came back.”
“After all, the area’s wide open in all directions—and this bright too.”

It was no wonder Ken’ichi had been shocked.

“Brother, shall we go see?”

“Wait! Since there aren’t any laborers left anyway—if we leave it alone like this, nobody will notice. Let’s keep it untouched till evening and go check once it’s dark.”

For once, Ken'ichi was the clever one.

Footprints and——The Copper Plate Map

Around nine o'clock that evening, Ken'ichi, Yōko, and Ayako, prepared as thoroughly as for an Arctic expedition, descended to the riverbed beneath Takadate.

“Brother, this path is rough—and there’s no moon either.”

Yōko and Ayako tumbled several times.
Since they had built embankments and forcibly dried up the river to walk through it, rocks of all sizes obstructed their path, making it very difficult to proceed as they wished.

“Should I turn on the flashlight?”

“If you do that, it’ll be visible from miles away!”

Though being scolded by Yōko, they somehow managed to reach the entrance of the hole they had located during daylight.

“Here it is.”
“Wait a moment—I’ll make it passable.”

Ken'ichi took out the pickaxe he had hidden among the rocks and struck with all his might.

Two strikes, three strikes—the hole gradually widened, and an entrance large enough to enter with ease if one merely crouched opened within the darkness.

“Alright, let’s go in. There might be toxic gas, so once we’re inside the hole, we’ll light a candle.”

Ken'ichi was accustomed to such things.
He lit a candle on the tip of the roughly two-meter-long pole he had brought.
He advanced by thrusting it out ahead.

The path sloped downward gradually, but the tunnel—carved through mudstone—proved unexpectedly safe. Though water stains coated the footing beneath them, the stone pavement laid eight hundred years prior remained pristine, leaving no cause for concern.

The stone pavement had been laid in a single path. Tracing its course, they found themselves ascending gradually until they reached a hall measuring roughly ten meters square.

“Huh?”

Yōko let out a sharp cry.

“What’s wrong, Yōko-chan?”

“There are human footprints!”

“Huh?!”

With two flashlights and one candle—rudimentary as they were—the stone pavement laid rather skillfully beneath them bore water stains three or even four centimeters deep in places. And upon this surface were imprinted two, three, five—no—far more unmistakable human footprints.

“They must be footprints from someone in the Fujiwara period.”

Ken’ichi, being the athlete he was, immediately took an optimistic view of things, but Yōko and Ayako were not so carefree.

“But there are studs on the heel marks, you know. Would people from eight hundred years ago have worn such shoes?”

“Hmm.”

Ken’ichi also groaned.
If someone wearing shoes had come in here, this spelled serious trouble.

“Brother, when you saw it during the day, what was the entrance of the hole like?”

“It was blocked with gravel, rocks, and mud.”

“Even though it had been sealed underwater for eight hundred years, could Brother really have pried it open so effortlessly with just a pickaxe?”

“Now that you mention it, that’s right.”

“Could this hole be an old escape tunnel unrelated to the treasure vault?—Perhaps your father discovered it once, found nothing, and had the entrance sealed?”

Yōko’s train of thought grew increasingly meticulous.

“Huh?”

This time, it was Ayako who found something.

“What?”

“What could this be? It’s really heavy, you know.”

It was a thin copper plate about half a meter square, and Ayako could barely lift it with her hands.

“Ah! This must be the blueprint of the treasure vault!”

“Let me see.”

The three of them instinctively drew their heads together.

The embankment had broken—water tore through into the tunnel with tremendous force.

It was a thin copper plate finely engraved with a map, half-green with corrosion, but by no means illegible.

“I get it now!”

Ayako suddenly raised her face and looked around in all directions.

“What’s wrong, Ayako-san?” asked Yōko.

“This copper plate map hasn’t been seen since around the time the diver was killed.”
“So I think it might be like this—back when there was still water in this hole, the diver came in here carrying this copper plate map. While he was searching for the secret passage to the treasure vault, his air supply tube was cut, and he suffocated to death right here.”
“The body was pulled up from the entrance with a rope, but the copper plate had been dropped when the diver died and was left here.”

At Ayako’s words, Yōko and Ken’ichi involuntarily shuddered and exchanged glances.

“Then who sealed the entrance?” asked Yōko.

“It must have been Father. If the water disappeared, people would find it, so he blocked the hole and withdrew to Tokyo.”

There was no longer any room for doubt.

“In that case, let’s use this copper plate to search for the secret underground passage leading to the treasure vault.”

Ken’ichi removed the candle from its holder and took it over to the copper plate Ayako was holding. As long as they had this map, the eight-hundred-year-old secret would be unraveled, the gold and silver treasures—mementos of the Fujiwara family’s glory—would be obtained, and the stigma of Dr. Tachibana, who had been branded a fraudster and died, would be cleared.

“Oh? That’s strange.”

Ken’ichi suddenly looked around.
Though there was no wind, the flame of the candle in hand was swaying unsteadily.
“What’s that sound?”

Ayako pricked up her ears.
A terrifying sound of unknown origin was approaching, making the ground rumble.

“The embankment might’ve breached! We need to get outside now!”

Yōko quickly grasped the situation.

“Alright, I’ll hold the copper plate!”

Ken’ichi tucked the important map under his arm and dashed off as if to grab Ayako and Yōko’s hands. No—he tried to dash out, but upon exiting the roughly ten-meter-square hall and attempting to enter the tunnel leading outside, he froze in his tracks.

“Ah!”

Terrifying water beyond imagination rushed into the tunnel like a torrent from the hole’s entrance, filling it entirely.

Swimming against this ferocious torrent surging through the tunnel would have been impossible even for the world’s greatest swimmer.
Moreover, the water filled the tunnel completely, leaving no space to lift one’s head, and the tunnel itself stretched over thirty meters long.

Gradually, the water began soaking into the underground hall, encroaching upon the very ground where the three of them stood.

“What should we do, Brother?”

Even Yōko turned pale.

“Why don’t we look at the map and search for the path to the treasure vault?”

In times like these, even timid Ayako remained calm.
However, even if they took a flashlight and candle and pored over the copper plate map, the secret underground passage to the treasure vault was unlikely to be found in an instant.

Desperate straits—a tunnel of darkness and water

“Oh, why isn’t the water rising?”

Yōko had finally regained her composure.
If she didn’t panic, this girl’s excellent mind would cut through difficulties like a circular saw.

“Come to think of it, the water doesn’t seem to be reaching here,” said Ken’ichi.

“The water from the tunnel entrance is flowing in normally, right? The water must be draining somewhere, I tell you.”

Yōko swung her flashlight around and took two or three steps down into the water at her feet.

“Brother, there’s a large fork in the path here!”

“Let me see.”

Ken'ichi and Ayako also waded into the water.
When they looked where Yōko pointed, they saw a terrifyingly massive surge of water rushing into the tunnel from the entrance—pooling briefly before the hall—then flowing slowly and steadily into the large right fork.

“Shall we go take a look?”

There was no longer any time for hesitation. The force of the water rushing into the tunnel showed no signs of abating; the hall’s expanse was limited, and the air—stagnant for eight hundred years—grew increasingly murky with three people inside, evident both in their increasingly suffocating chests and in the candle’s weakening flame.

“Brother, let’s go.”

For about twenty meters from there, the three of them waded forward, submerged up to their chests, as if swept along by the rather fierce water current.
Ken’ichi placed the copper plate atop his head and held a candle aloft in one hand; Ayako, brandishing a flashlight, followed behind him; and bringing up the rear was Yōko, also carrying a flashlight, proceeding with unsteady steps.

“There’s a rock here—the left side’s deep!”

Ken’ichi occasionally said that.

Like an ox’s plodding pace, another ten meters or so.

“Ah!”

Ken’ichi unintentionally lost his footing and fell into the water.
It suddenly grew deeper.
The skilled swimmer quickly stood up, but the candle was washed away somewhere.

“Brother, I can’t touch the bottom!”

“Swim over here!”

Ayako and Yōko could swim a little, but with their shoes on and wearing kimonos—not to mention trying to keep their flashlights dry—it was a tremendous struggle.

“Ah!”

A ferocious, massive wave—perhaps the tunnel entrance had suddenly collapsed—swallowed the two girls in an instant, causing them to drop the flashlights.

Darkness as if painted over filled every direction.

“What’s wrong, Ayako? Yōko?”

Ken'ichi bellowed.

“Here, Brother!”

“I’m here.”

Fortunately, both Ayako and Yōko seemed to have crawled up to shallower ground, but with the candle and flashlight lost, the darkness became so absolute they wouldn’t have noticed if someone pinched their noses.
To either side stretched hollowed-out rock; ahead and behind surged water—its force swelling ever fiercer, as if the tunnel’s mouth had widened.

“Brother.”

“Ayako-san.”

“Yōko.”

The three groped their way forward through the blackness until their hands found one another.

At that moment, on the embankment of the Kitakami River, bathed in moonlight filtering through the clouds, someone was diligently tearing down the embankment, relentlessly channeling water into the tunnel’s mouth.

How could Ken’ichi, Ayako, and Yōko possibly survive?

A pale faint light pierced through the water——

Ayako—the bereaved daughter of Dr. Tachibana, who had entered the tunnel beneath the Kitakami River’s riverbed to uncover Hiraizumi Palace’s secrets and obtained a copper plate engraved with a line-etched map of the Underwater Palace—alongside her friend Yōko and Yōko’s brother Ken’ichi Midorikawa, the renowned swimmer, had been swept away by a raging torrent after an unknown party suddenly breached the embankment. Now they faced near-certain death in the pitch-black darkness of the tunnel.

“Hang in there, Yōko-chan, Ayako-san!”

Supporting the two girls with both arms in the raging torrent that submerged them up to their chests, Ken’ichi Midorikawa continued his desperate struggle.

“Brother, what’s going to happen?”

Yōko, usually the most cheerful and quickest-witted of them all, now lacked even the composure of Ayako—who remained silent and sorrowful—when caught in such a predicament.
Clutching tightly to her brother’s shoulder, she could focus only on the steadily rising water level inside the tunnel.

“Yōko-chan, you shouldn’t worry so much—I’m right here with you!”

Ken’ichi squared his broad, muscular shoulders and declared firmly.
Ken’ichi Midorikawa, the great swimmer who held several Japanese championships, was a boy you could rely on more than any great person in times like these.

The three of them, pushed along by the raging current, advanced another twenty meters or so.
During that time, their feet were swept away countless times; they were knocked sideways into the water, fell into terrifyingly deep holes, and nearly swallowed water more times than they could count.

What troubled them most was not only that the water in the tunnel was steadily rising, leaving them barely able to keep their heads above it, but also that the air was growing increasingly foul.
Since the force of the incoming water showed no sign of abating, if they continued to dawdle like this, within thirty minutes, all three of them would either suffocate or drown—in any case, there would be no hope of survival.

“We can’t advance another step—the tunnel’s full of water.”

Ken’ichi unintentionally blurted this out.
Even with their heads pressed against the tunnel ceiling, the water was already past their chins and threatening to enter their mouths.

“Brother.”

“We’ll turn back or find another way.”

Ken’ichi decisively turned on his heel.

“That’s impossible!”

Yōko, startled, clung to her brother’s neck. Retracing the hardships they’d endured to reach this point would be grueling enough—but worse still, even if they turned back, there seemed to be no other escape route.

“But we can’t keep going like this.”

Even Ken’ichi could do nothing against the water surging through the tunnel.

“What’s that? There’s just a faint glimmer piercing through the water—don’t you think?”

Ayako pulled Ken'ichi's arm and showed him the water ahead they had been moving through.

“That’s strange.”

When they brought their eyes close to the water’s surface, they found a pale blue light—just a faint glimmer—hazily shining through the water ahead.

“Was there a moon tonight, don’t you think?”

Yōko suddenly asked an odd question.

“The full moon was about three days ago, so right now might be around moonrise,” said Ken’ichi.

“Then it must be moonlight—this is the tunnel’s exit, though we didn’t realize it until now—the moon came out and shone on the water, so that’s why it’s faintly lit like that, don’t you think?”

Yōko finally began to put her brilliant mind to work.

Life or Death—The Trio Dives

“Should I go check it out?”

Ken’ichi had already begun preparing to dive. He had no idea whether they would be diving meters—no, tens of meters—but now was not the time to voice such thoughts.

“Let us go together, Brother.”

“It’s dangerous, Yōko-chan. Why not wait here until I sound out the shallows and return?”

“But we know we cannot linger here long. If it is too perilous for Brother to go alone, then those of us remaining would have no hope of survival either—would we not, Ayako-san?”

“Yes.”

That was truly as Yōko had said.
If Ken’ichi alone could go and return, then the three of them should be able to go as well; and if even Ken’ichi alone couldn’t escape, then the three would have no path but death.

“Alright—if that’s your resolve, we’ll go together. I’ll do everything I can, but don’t get in my way. Whether we live or die, we’re in this together.”

“Brother.”

“Yōko-chan, grab my band from the left; Ayako-san from the right—don’t let go! And dive as close to the bottom as possible! The water’s right up to the tunnel ceiling—if you get sucked against it, we’re done for!”

“It’s all right, Brother.”

“Alright, let’s dive!”

The aquatic athlete Ken’ichi Midorikawa plunged into the swirling water like a fish, two girls dangling from his waist.

His target was the faint glow ahead—impossible to tell whether it lay dozens of meters away—but colliding against the rock-hewn tunnel walls at every turn, Ken’ichi desperately churned his limbs through the water. What felt like thirty minutes—no, in truth mere three minutes, though it might as well have been three hours—he endured this suffocating trial, driving himself blindly forward through the murk.

The two girls flanking him did not hinder Ken’ichi in the slightest, but since there was no way they could keep up with the star athlete underwater, they must have swallowed some water. Every so often, their hands gripping his band would slacken, yet the light guiding the three through the water grew no brighter than before.

Ken’ichi summoned his last reserves of strength. Meanwhile, Ayako—who had been gripping the band on his right—thrashed so violently in the water, her own strength spent, that even Ken’ichi could clearly perceive her struggle. Then abruptly, she released her hold and floated upward with a smooth, swift motion.

It's dangerous—! Though underwater speech was impossible, Ken'ichi, startled, pursued her. Having already burned through his last reserves of strength, even someone of Ken'ichi's caliber could endure no more.

“Ah!”

Ken'ichi involuntarily let out a cry.
As he floated his body up, before he knew it, his face was above the water, and he took a deep breath of the refreshing night air.

The beauty of the moon, now perfectly framed by the shade of the grove.

While hurriedly pulling Yōko up, Ken'ichi swam, working one arm.

Fortunately, Ayako—half-alive—was also floating right nearby.

“Thank goodness.”

After all, it was a deep pool in the river, and from there to the shore was no great distance.
Ken'ichi hauled the two girls up to the shore as if he were lifting straw bales.

The Project and the Copper Plate—Negotiations Demanding Their Handover

Yōko and Ayako had swallowed a considerable amount of muddy water and had to rest for about three days.

Ken’ichi, true to his vigorous self, spent that time rallying the laborers who had arrived from Tokyo to rebuild the once-destroyed embankment and drain the water from the tunnel.

The copper plate map that had been dropped in the tunnel was fortunately retrieved by Ken’ichi without incident, having sunk into the mud near the exit.

But while Ayako and Yōko remained unwell, even he couldn’t venture into the tunnel alone.
With no alternative, as he supervised laborers diligently digging out the riverbed, widening the tunnel entrance, and reinforcing the embankments, he found himself strolling about—when a man fishing beneath the shade of a willow tree on the bank, as if wary of prying eyes, quietly beckoned to him.

“Me?”

“Well, I have something I’d like to discuss. Why don’t you sit right there? I’ll talk while I fish—this spot’s great for catching them, you know.”

The man wearing black Lloyd glasses for UV protection, an ill-fitting Western-style suit, and a helmet began in this manner.

“What is this about? I don’t know you—”

Ken’ichi had grown thoroughly cautious.

“You don’t need to know who I am. I work at a Tokyo school—using summer break to fish through Tohoku’s rivers and lakes. But two or three nights back, I spotted someone busily wrecking this embankment. Since you’re overseeing this construction project, thought I’d mention it.”

“What did this embankment-wrecker look like?”

Ken’ichi also held his breath.

“A pale, modern young man—oblong face, slightly receding chin, his hair glistening like a dragonfly’s eyes—”

“Ah! That man?”

“Do you know him?”

“No—he’s someone I’ve seen before.”

“In any case—don’t let your guard down! Seems something’s been lurking around you and those sisters of yours nonstop—ah! My apologies for overstepping! I’ll just keep quiet and fish for trout—around here trout rise on hot summer evenings.”
“Though this rod’s no good—you’d need a hand net.”

The helmeted man, who seemed fond of fishing, continued to gaze intently at the movement of the float on the water’s surface. He was likely still in his thirties, but his skin, sunburned to the color of persimmon-tanned paper, and his somehow intellectual manner of speech made him an altogether mysterious figure—the sort rarely seen in these parts.

With a somewhat oppressed feeling, Ken’ichi thanked him and returned to find Ayako and Yōko already up and preparing lunch with O-Taka-san.

“Brother, someone important has arrived!”

When she caught sight of Ken’ichi, Yōko rushed out and whispered quietly.

“What’s up, Yō-chan?”

“The president of Karasaki Trading and his secretary—that secretary’s the weird flashy Westernized guy we ran into in Sendai. He’s been prowling around here for over a week now.”

As for that flashy Westernized guy with the dragonfly-like hairstyle—he must be the very troublemaker that peculiar fishing gentleman had earlier told him about destroying the embankment.
Possibly,the same person might have been responsible for stabbing Hanai,the student.

Ken’ichi,bracing himself for what seemed likely to become a difficult negotiation,pushed open the door to a six-tatami room in the cottage that was neither quite a living room nor a guest room.

“Ah,Mister Midorikawa—I’ve been waiting.You’re aware,I presume?I am Karasaki Sōnosuke,the investor in this Hiraizumi excavation project.This here is my secretary,Sugimura Sangorō.A pleasure.”

“...”

Ken’ichi silently greeted him and sat down across from the businessman with an old-fashioned mustache.

The wind blowing through the window with fresh green leaves—outside, the cabin stood perfectly refreshing amid a deep green like the seabed, yet inside the room, an oppressive air stagnated like an old swamp.

“Now then, with Dr. Tachibana gone, as the one who invested half, I am the rightful successor to this project. I demand you hand it over immediately. And that copper plate map you’ve recently come by—I’ll be claiming that too, as is my rightful due.”

Karasaki Sōnosuke was domineering. Seeing his counterpart as a mere boy, he likely intended to resolve matters in one sweeping move.

"I don't know about legal technicalities, but if Dr. Tachibana has died, the project should naturally pass to his heir, Ayako-san."
"Ayako-san's guardian will be formally appointed in time—if you take issue with this, please consult the legal counsel. We cannot surrender the copper plate over such procedural matters."

Ken’ichi was not about to back down either—the great athlete once hailed as the champion of the waters met Karasaki’s pressure with formidable resolve.

“That’s absurd! Who do you think has been funding this project all along? Without even consulting me—”

“It’s my father—Kentarō Midorikawa. He’s newly investing to support Ayako-san. Since this isn’t a corporation or anything like that, I’ve heard both the investment and continuation of the project are entirely at his discretion.”

“Mr. Midorikawa? What a preposterous thing he’s gotten himself into!”

Karasaki Sōnosuke quivered with rage, but since Kentarō Midorikawa was a prominent businessman and Ken’ichi’s assertions were irrefutable, there was nothing he could do.

“I’ll return to negotiate another time—this absurdity has gone too far!”

“Be my guest.”

Leaving Ken’ichi behind, he brusquely urged his secretary and withdrew.

The copper plate had been stolen—but the film remained.

“Brother, where’s the copper plate map?”

“It should be in the closet in the six-tatami room.”

“It’s not there,” said Yōko.

“What?!”

Ken’ichi and Ayako rushed together into the six-tatami room; the log-framed window’s glass door stood wide open, the cupboard left ajar, and the copper plate inside was nowhere to be seen.

“They got us!”

Ken’ichi suddenly leaped out of the opened window, but the forest—still too early for moonrise—was a pitch-black darkness where he couldn’t see an inch ahead.

The thief must have taken advantage of everyone being in the next room having dinner to enter through the window.

“There should be footprints.”

When they looked in the light of the lamp that Yōko had extended by lengthening its cord, there on the soft soil beneath the window—besides Ken’ichi’s large bulldog-shaped footprints—were deeply imprinted, pointed and delicate footprints!

“That’s him!”

In Ken’ichi’s mind arose a vivid image of the pale secretary—Sugimura Sangorō’s impeccably Westernized appearance. In these mountains, who else but that secretary could possibly wear such stylish shoes?

“This is bad. Without the map, we can’t dig even one shaku (approximately 30 centimeters) further.”

Ken’ichi was completely dejected.
The copper plate map, which had once been lost with the diver’s death and nearly doomed the project, had been stolen again just as the excavation was finally showing promise.

“Brother, even if they stole the copper plate, we still have the map itself!”

Yōko said something unexpected.

“How could that be? The copper plate *is* the map!”

“Oh, exactly! But I thought this might happen, so I photographed that copper plate—over and over, dozens of times.”

“Got ’em! Show me that!”

“No good—it’s still on film. In a place like this, we can’t develop or print it, you know.”

“I’ll go to Ichinoseki and back—hand over the film.”

Ken’ichi was an athlete—when it came down to it, he knew not a moment’s hesitation.

“I thought relying on a single photo was too risky, so I took six of them.”

Taking the film from Yōko’s hand, Ken’ichi rushed out of the hut, too impatient to even throw on his jacket.

They entered guided by the photographs—in the tunnel was poison gas.

Ken’ichi returned from Ichinoseki much sooner than expected, and around 1 a.m. that night, he held six photographs in his hand, looking thoroughly triumphant.

“Yō-chan, this is a huge success! Every single photo turned out perfectly! Now that we have these, that heavy copper plate’s nothing but dead weight!”

When they looked at the photographs laid out on the table under the electric light, the results were splendid for Yōko’s skill—of the six, at least two were as clear as if taken by a professional.

“Well, it’s odd that my photos are actually useful.”

Even in her elation, Yōko seemed slightly embarrassed.

“By the way, as you can see even in these photos, there are some scratch-like marks outside the map. They seem to be characters added later to the copper plate, but we just can’t read them.”

...

When they held up the clearest photo to examine against the light，sure enough，near its edge something like scratched characters could be seen．

“On the copper plate itself you couldn’t see them because of rust—but when photographed，blue rust shows up white，making those scratches stand out！Anyway，leaving it like this won’t do any good，so I had them plate and enlarge the film．A messenger should bring it by tomorrow evening．”

Whatever secrets the scratched characters revealed in the photograph of the copper plate might hold—be that as it may—it remained a fact that once dawn broke, the excavation of Hiraizumi Palace resumed with renewed vigor.

Karasaki Sōnosuke, his secretary Sugimura, and the man with Lloyd-style glasses were nowhere to be seen all day, and the Ichinoseki photo studio also failed to deliver the enlarged photographs before nightfall.

“What could be happening, Brother?”

Just as she was saying this, the man who had been guarding the tunnel entrance came running,

“It seems someone has entered the tunnel—the man who was guarding in shifts with me has collapsed at the entrance.”

He reported with a pale face.

“There!”

When they went to check the tunnel entrance, there indeed lay a man who appeared to have been struck on the head with a heavy object, still nauseous as two or three comrades tended to him.

“I’ll go check inside. You two stay here—it’s dangerous.”

Ken’ichi said this to Yōko and Ayako and dove into the tunnel.

“It’s all right. There are so many of us here at the entrance.”

The two girls also followed him in.

When the tunnel ended and they stepped into the underground plaza,

“Huh?”

Ken’ichi came to a halt.

“What? Brother.”

“It’s poison gas! Dangerous! Turn back!”

Ken’ichi, tucking the two girls under his arms, paid no heed to the scrapes and bruises he incurred as he blindly rushed back toward the tunnel entrance.

“Is that the poison gas, Brother?”

“Ah, no mistake—it’s poison gas. That smell—I’ve sniffed it countless times in the school lab.”

“Why would there be poison gas here?”

“It can’t occur naturally—someone made it. In fact, in that small room beyond the plaza, I saw a human figure collapsed.”

“Let’s help them—whoever they are.”

“You can’t go in there without a mask.”

“The masks should be in the hut—people often get overcome by natural poison gas during underground explorations. Many died from gas during King Tutankhamun’s tomb excavation too, I hear. Father once said, ‘I’ll prepare masks and go—’”

Ayako recalled a clever idea.

“That’s perfect timing!”

When Ken’ichi rushed off, O-Taka-san brought out three sets of sturdy gas masks and oxygen generators from the storage shed.

Something more precious than gold—The Grand Palace Bathed in Daylight

Ken’ichi, Yōko, and Ayako put on poison gas masks and plunged into the tunnel.

When they went into the small hole beyond the plaza and looked, even before swinging their flashlights around, two people lay collapsed as if dead.

When they peered inside, there lay Karasaki Sōnosuke and his secretary Sugimura Sangorō. If they hadn’t been wearing masks, what a loud cry of surprise the three would have let out.

The fact that a crudely made poison gas generator lay discarded at the plaza entrance suggested that whoever had seen the two men enter the tunnel had stealthily followed them, placed it there, and then fled.
Fortunately, the poison gas generator was faulty and had not emitted gas properly. As a result, Karasaki Sōnosuke and his secretary appeared to be barely clinging to life, their breaths faint but steady.

Ken’ichi, Ayako, and Yōko dragged the two men out of the tunnel.

Exposing them to the fresh night air and tending to them a little fortunately restored their senses, so they had the guarding laborers carry the men and ultimately brought them to the hut—by then, it was already nearly ten o’clock.

“No—Mr. Midorikawa, not a word of that. If not for your bravery and the young ladies’ wisdom at work, both Mr. Sugimura and I would have died right there.”

Karasaki Sōnosuke bobbed a bow from his bed, and now even his old-fashioned sideburns looked thoroughly disheveled.

“Who brought in the poison gas generator?” asked Ken’ichi.

“I don’t know—no, I feel like I do know, but without evidence, I can’t say.”

“Who is that?”

“There will be an opportunity to speak of it eventually—but tell me, Mr. Midorikawa, how should I repay this debt of saving my life?”

“Please withdraw from this excavation project. If there happens to be any profit, we will distribute it according to your investment amount.”

“That’s nothing. As for my investment amount—well, now that I mention it, it’s just a small sum.”

“I am well aware of that.”

“Shall I return the copper plate as well?”

Karasaki Sōnosuke appeared thoroughly defeated.

“No, we don’t need such a thing. Rather than that, please ask Secretary Sugimura who stabbed Hanai the student and tried to kill us by destroying the embankments.”

Ken’ichi posed his final question.

“You seem to suspect me, but it wasn’t me. As for who stabbed the student—well, regardless—the one who destroyed the embankments was that man with Lloyd glasses who often fished around there.”

“What?!”

Secretary Sugimura’s words were utterly unexpected.
Just at that moment,

"A photo has arrived from Ichinoseki."

When they tore open the package of enlarged photographs O-Taka had brought, inside lay four prints. These not only showed Hiraizumi Palace's underground vault diagram more clearly than the original copper plate, but near the edge bore characters scratched with what appeared to be a small knife.

—Takiyama's after me. Tube severed. Dying now—

Though wildly scrawled, every word stood perfectly legible.

“Ah!”

O-Taka-san collapsed onto the floor.
She had been examining the enlarged photographs, but upon seeing that her husband, in his death throes, had written the name of the one who killed him, she lost consciousness.

“Come to think of it, Takiyama must have killed Old Servant Shōhei too! Those three movie programs existed precisely because he slipped out alone midway through, murdered Shōhei, then returned to the cinema.”

Yōko remembered the mystery of the programs she herself had uncovered.

“He wanted exclusive control over the documents in that safe—and besides, Old Servant Shōhei might have known Takiyama killed that diver.”

Karasaki Sōnosuke added his voice.
It later became apparent this man was no true villain—merely overzealous about profit and somewhat arrogant by nature.

Secretary Sugimura Sangorō was a fashionably Westernized yet shallow man, utterly useless and incapable of doing either good or evil.

“Let’s send a telegram to Tokyo and have Assistant Takiyama restrained.”

Ken’ichi stood up.

“There’s no need for that. I think that Lloyd-glasses guy who’s always fishing is definitely Takiyama—he’s come here in disguise.”

Ayako interjected.
Since Dr. Tachibana’s daughter had seen through him, Assistant Takiyama could no longer keep up no matter how he disguised himself.

That very night, a police squad arrived from Hiraizumi; the next day, reinforcements from Maesawa and Ichinoseki joined in. When they conducted a manhunt across Hiraizumi, Takiyama—who had pitched a tent in the mountains behind Chūson-ji Temple—was captured without resistance.

It was Assistant Takiyama who killed the diver, drove Dr. Tachibana into a corner, murdered Old Servant Shōhei, breached the embankments, and stabbed Hanai.
Takiyama was truly a quintessential villain who had committed such terrible deeds to monopolize the wealth buried beneath Hiraizumi.

When he stubbornly refused to confess, the prosecutor in charge—having been inspired by the mystery of the movie programs Yōko had told him about—questioned him about the plot of the film he claimed to have seen that night. Since he knew nothing of it, they finally realized he had killed Old Servant Shōhei, and with that, he confessed to everything.

That was a story for much later.

The day after Takiyama was restrained, Midorikawa Kentarō—Ken’ichi and Yōko’s father—arrived in Hiraizumi.
On this day, at last, the great treasure vault beneath Takadono and Hiraizumi Palace—which had concealed the glory of four generations of the Fujiwara clan—was to be opened.

When they passed through the tunnel and opened the underground chamber beyond the square, there on the mountain’s far side lay treasures hidden for eight hundred years, exposed to midsummer sunlight for the first time.

“Ah!”
Ken’ichi, Yōko, Ayako, Ken’ichi’s father Kentarō, O-Taka-san, Karasaki Sōnosuke, and his secretary all let out cries of surprise.
Within the secret chamber—built up with stones, a secret chamber of unparalleled splendor and security—there was not a single grain of gold dust or a single coin.
What remained were utensils, furnishings, and garments that once boasted of the Fujiwara clan’s four-generation splendor—now corroded by time into objects useful only for archaeological and historical reference—alongside piles upon piles of mortuary tablets, Buddhist implements, ancient copied sutras, and magnificent stacks of historical documents.

“This is truly remarkable! If scholars saw this, there’s no telling how overjoyed they’d be. No wonder Dr. Tachibana devoted himself so passionately to excavating it.”

Midorikawa Kentarō said profoundly.

“The gold—where’s the gold?”

Karasaki Sōnosuke lingered restlessly.

“Gold is something you produce through work. The real gold is what you earn by the sweat of your brow—the root of all error lies in believing gold can be found at the bottom of the sea or buried in the ground.”

“……”

Midorikawa Kentarō turned toward Ken’ichi, Yōko, and Ayako and continued.

“This is more precious than gold. Let’s donate it to a museum or the Imperial University. I’ll cover all expenses incurred so far. Miss Ayako will become Yōko’s sister from today onward—is that acceptable? The very idea that gold lies at the bottom of the sea or buried in the earth—fighting and killing over such delusions is where the error lies. Dr. Tachibana undoubtedly never gave a thought to gold; it was society that stirred up this frenzy, convinced they’d dig out riches. You cannot fathom how much more precious scholars find these ancient documents, old copied sutras, and tattered tools than mere gold.”

While Midorikawa Kentarō was saying this, Karasaki Sōnosuke, unable to bear it any longer, slipped away furtively, and Yōko and Ayako hugged each other, crying tears of joy.

After eight hundred years emerged into the world—the midsummer sun blazing upon the great palace. What brightness it was!