The rain had not stopped since morning. It came in light sheets across Tokyo's Grand Line, dripping from the ribs of the amusement park's steel bones, turning the laughter above into something ghostly, hollow. Neon lights swam across puddles like bleeding memories.
Akio Hukitaske stood beside Detective Yakahura Mizuhashi in the dim backlot of the park, where service tunnels gaped open beneath a rusted metal hatch. Hikata Yakasuke and Rumane stood a few steps behind, exchanging uneasy glances.
"You sure about this?" Hikata muttered, rubbing his neck, his wristband glinting faintly in the shadows. "We've already seen enough creepy stuff for one trip. Maybe we call this off, yeah?"
Akio adjusted the strap of his sword case over his shoulder, his voice calm but edged with tension. "If the Red Smoke remnants are here, we don't have the luxury to turn back. We end this before someone else gets hurt. Plus these bands are annoying Hikata."
Rumane exhaled softly, folding her arms. "You're assuming this isn't a trap."
"It probably is," Mizuhashi said grimly, flicking on his flashlight. The beam carved a thin path into the black below. "But if the Helix Project left anything behind — even data, samples, or schematics — we need to see it before they do."
The word Helix hung heavy. Akio felt the weight of it settle over his heart like a stone. Memories clawed their way up — the night of the burning lab, the screams, the collapse of glass corridors filled with green mist. The Emerald and Black Blades had sung in those days around years and a year ago during the collapse and Murakaze days, and he had sworn never to let the Helix's twisted science rise again.
But promises were fragile things.
The descent began slow, metallic steps echoing beneath their feet as they climbed down the service ladder. The air below was damp, electric, filled with the smell of rust and rot. Hikata coughed once, the sound sharp and hollow.
"Man, this place smells like a sewer married a scrapyard," he grumbled. "Remind me again why theme parks have secret tunnels? Who even builds this stuff?"
"Maintenance corridors," Mizuhashi replied. "Every major park has them — to move workers, materials, and, in the case of Grand Line, store older rides before they were rebuilt. But after the fire in '09… most of it got sealed off."
"And yet someone reopened it," Rumane murmured. Her flashlight scanned graffiti-smeared walls — strange symbols half-erased, streaks of old oil, and what looked like red powder.
Akio knelt and touched the residue. It came off faintly sticky. He rubbed it between his fingers. "Red smoke compound."
Mizuhashi's eyes narrowed. "They were here."
Hikata tried to joke, but his voice was thin. "Yeah, maybe they were just redecorating?"
No one laughed.
They pressed forward, boots sinking in thin puddles, the sound of dripping water filling the silence between heartbeats. The deeper they went, the colder it became — the kind of cold that felt alive, crawling beneath the skin.
The tunnel began to change. Steel gave way to concrete, then to something older — reinforced stone and heavy iron doors that looked far too advanced for mere park infrastructure. The light from their torches caught lettering scorched into one of the doors:
Y.L. Subsection 04 — Access Restricted.
Yaka Lab.
Akio's pulse quickened. "They built under here too."
Mizuhashi nodded grimly. "The Helix Project used hidden research wings beneath public sites. The Grand Line was one of their front companies before the lab's collapse. I didn't think this one survived."
Rumane traced the letters with her gloved hand. "Then the Remnants must have found their way in. Maybe they're looking for something left behind."
"Something like them," Akio said softly, eyes hard. "The failed prototypes."
The detective gave a slow nod. "If they're trying to revive the Helix, even fragments of its work could be catastrophic."
The door groaned open after Akio used one of the Murakaze forged blades to cut through the locking mechanism. Inside, a wave of stale air hit them — heavy with the scent of chemicals and old decay.
Rows of shattered test tubes lined the walls. Cracked consoles flickered faintly, their ghostly green lights pulsing like dying stars. Dust clung to every surface like snow.
It was as if time had stopped mid-breath.
"Holy hell…" Hikata whispered. "This is it, huh? The real deal?"
Rumane knelt beside a rusted terminal. "Not much left. Power's unstable, but…" She tapped a few keys, coaxing a weak hum from the screen. "I might be able to bring up some logs."
Akio moved deeper into the room, flashlight trembling slightly. His reflection blinked back from a shattered glass chamber — inside it, scorched restraints and faint claw marks etched into steel. The memories came again — the screams of failed experiments, the faces of scientists who'd traded humanity for discovery.
"Akio," Mizuhashi said quietly. "You were here once, weren't you?"
He hesitated. "…I was the one who burned it."
The words came out like confession.
Rumane's eyes softened, but she said nothing. Hikata looked away. The silence held the echo of all they'd lost — friends, allies, a version of themselves that had died with the Helix.
Then, faint footsteps.
Akio froze. The others fell still.
A metal clang echoed down the corridor behind them, followed by the faint hiss of air pressure. Someone else was in the tunnels.
"Contact?" Hikata whispered, already reaching for one of Akio's emergency vials that Akio had given him for emergancy purposes and 1 out of the 4 he was given, and ready to combine the skills with his fighting skills from the goofy jobs he already has, on top of it all.
"Hold," Akio ordered softly. "We don't know who it is yet."
The footsteps drew closer — deliberate, confident. Then, from the darkness, a faint orange glow appeared, illuminating a silhouette in a long coat. A person stepped into view, his face partly hidden beneath the rim of a soaked hat.
Detective Mizuhashi's hand tightened on his flashlight. "You…"
The stranger smiled faintly. "Still chasing ghosts, I see, Mizuhashi."
Akio's grip tightened on the sword case. "Who are you?"
The stranger tipped his hat, revealing pale eyes that gleamed like glass. "Detective Jinji Hazukata, formerly of the Hokkaido Division. Or at least… what's left of it."
Hikata blinked. "Wait, the Jinji Hazukata? The guy who cracked the '89 Sapphire Case?' You're supposed to be retired!"
"Retirement's boring," Hazukata said dryly. "Besides, when the past starts to crawl back from its grave, you either dig it up yourself or it buries you instead."
Mizuhashi exhaled through his nose, tension easing slightly. "You always did like dramatic entrances."
"Only when the company's worth it," Hazukata replied. His gaze swept over Akio, Rumane, and Hikata, lingering on the sword case. "So you're the young one they call the Phantom's brother. I've heard of you."
Akio frowned. "Then you know why I'm here."
Hazukata nodded. "I know what you're chasing. But it's not the Helix anymore — it's the shadow of what came after."
Akio's brow furrowed. "The Red Smoke Bandits."
"Not just them," Hazukata said, lowering his voice. "They've merged with what's left of the Yaka Lab's black cells. The Red Smoke were mercenaries. But these people? They're trying to rebuild the Helix under a new name."
Mizuhashi tensed. "You have proof?"
The older detective handed him a weathered folder, edges burned. Inside were photos — aerial shots, data logs, blueprints of a new structure being erected near the Tokyo Bay industrial district. The insignia stamped across the blueprints made Akio's stomach twist.
A crimson spiral.
"The Recoil Division," Hazukata said softly. "The Helix's final contingency plan. They've been working in silence, waiting for a moment just like this — when the world forgets."
Rumane's fingers tightened on her sleeve. "And the amusement park?"
"Front cover," Hazukata said. "The perfect place to hide old tunnels and experimental caches under the noise of a thousand screams."
Akio took a slow breath, mind racing. Everything fit — the detonating wristbands, the strange compounds, the timing of the client's invitation. It was all a lure to draw them back here… back where it began.
He looked at Hazukata. "Then we're already part of their experiment."
Hazukata met his gaze evenly. "Exactly. The Red Smoke remnants want your vials, your blades — the last living proof of the Murakaze lineage. And they'll burn the city to ash if it means resurrecting the Helix's ghost."
Silence followed. Even Hikata couldn't find a joke to cut through it.
They stayed in the tunnels a while longer, gathering files, snapping photos, mapping exits. The cold air hummed faintly with static — as though the walls themselves still remembered the experiments conducted there.
As they prepared to leave, Akio paused at the shattered containment pod. Inside, beneath the grime, something faintly glimmered — a fragment of crystal, pulsing faintly green.
Rumane stepped closer. "Is that—?"
"Emerald Helix residue," Akio murmured. "I thought it was destroyed."
He picked it up carefully, sealing it in a small vial. For a moment, the light reflected in his eyes — sorrow and determination intertwined.
"Maybe," he said quietly, "the Helix never really died. Maybe it just went to sleep."
Mizuhashi put a hand on his shoulder. "Then let's make sure it never wakes."
They climbed back toward the surface, the sound of the park slowly bleeding back into existence — laughter, the hum of rides, the faint call of carnival music.
But beneath it all, the tunnels whispered.
As the four emerged into the twilight rain, Hikata sighed heavily. "You know, I was kinda hoping this would be a normal trip. Maybe win a plush toy, eat bad food, not uncover a conspiracy of mutant scientists under a roller coaster."
Rumane gave a small smile. "That would be too simple for you."
Akio said nothing. His gaze lingered on the park — the bright lights, the children's laughter, the illusion of peace above the veins of something terrible.
Hazukata adjusted his coat, rain dripping from the brim of his hat. "Enjoy the calm while it lasts, kids. Because the next move…" He glanced back toward the tunnels. "…won't come from us."
The thunder rolled across the sky.
And somewhere, deep beneath Tokyo's Grand Line, the faint hum of the Helix stirred again — a quiet heartbeat waiting to rise.
TO BE CONTINUED...