The "Yellow Line" at the Metropolitan Police Headquarters felt like a fortress wall. Evidence Room 4 was located in the basement, a place where the air was recycled and the silence was heavy. Even with the badge of a defense attorney, Arata felt the hostile stares of every officer in the hallway. To them, he wasn't just a lawyer; he was the man trying to let a "cop-killer" walk free.
"We shouldn't be here," Hana whispered, her sneakers squeaking on the linoleum. "Nosaku probably has this floor under twenty-four-hour surveillance."
"He does," Arata said, his eyes scanning the ceiling for cameras. "Which is why we're not looking for the door. We're looking for the gap."
They reached the door to Evidence Room 4. It was a heavy, biometric-sealed slab of steel. On the wall beside it sat the scanner the very one that recorded only two entries on the night of the murder: Detective Yatsurugi and the victim, Detective Kaito.
Arata knelt by the door frame. He wasn't looking at the lock. He was looking at the floor.
"Hana, give me the high-intensity blue light," he commanded.
She handed him the forensic torch. Arata clicked it on, and the floor illuminated in a ghostly neon. Most of it was clean scrubbed by the forensics team but he crawled toward the ventilation grate near the baseboard.
"Yatsurugi said he smelled burnt sugar," Arata muttered, his nose inches from the metal slats. "In chemistry, that's the smell of caramelization. But it's also the scent of burning sucrose a common component in homemade smoke bombs or... high-yield detonators."
"But there was no explosion," Hana countered. "Just a single gunshot."
Arata pulled a small pair of tweezers from his pocket and reached into the grate. He pulled out a tiny, translucent shard. It was no bigger than a grain of salt, but under the blue light, it glowed with a strange, amber hue.
"It wasn't an explosion," Arata said, his voice dropping. "It was a trigger. Hana, what happens if you combine a high-voltage power surge with a sugar-based chemical conductor?"
Hana's fingers flew across her tablet. "The sugar acts as a bridge. If you coat a wire in it, you can create a delayed short circuit. But Arata-san, that's for setting off fireworks or small charges. It wouldn't fire a gun."
"It would if the gun was already aimed," Arata said. He stood up and looked at the room's layout through the small reinforced window. "Look at the evidence table. That's where they were logging the Shinjuku heroin. If someone knew exactly where Yatsurugi would place his service weapon while he was handling the bags..."
Suddenly, the elevator at the end of the hall chimed. The sound was bright and jarring in the silent basement.
Click. Click. Click.
The sound of expensive leather shoes on hard tile approached. Arata didn't move. He knew that rhythm.
Shin Nosaku appeared around the corner. The dark red of his suit looked almost black in the dim basement lighting. He wasn't wearing his usual smug grin. His expression was as cold as the concrete walls.
"Trespassing in a crime scene, Ōgi-kun?" Nosaku asked. "That's a quick way to lose that license you're so proud of."
"I'm a defense attorney on an active case, Nosaku-san. I have a right to inspect the scene," Arata replied, standing his ground. He tucked the amber shard into a small glass vial in his pocket.
Nosaku stopped three feet away. The height difference felt more pronounced here in the cramped hallway. "You're looking for a ghost. A third person who entered a room that only opens for two sets of prints. You think you've found a 'trick,' don't you? A smell of sugar. A flicker of lights."
Nosaku leaned in, his voice a dangerous whisper. "I'll tell you what the sugar was, Rookie. Detective Yatsurugi had a packet of sweets in his pocket. He dropped them when he struggled with his partner. The power surge? The building's generator was testing. It's all in the report I'm going to hand to the Judge tomorrow. Everything you find, I've already turned into evidence against you."
Arata felt a bead of sweat roll down his neck.
Nosaku wasn't just prosecuting; he was anticipating. Every move Arata made, Nosaku was already there, turning the "truth" into a weapon for the state.
"Why go to this much trouble for one detective?" Arata asked. "Unless Yatsurugi wasn't the target. Unless the man he was investigating was someone you're protecting."
Nosaku's eyes didn't flinch. He reached out and straightened Arata's blue tie with a slow, mocking deliberation.
"In this city, the law is a cage, Arata. It keeps the animals in and the masters safe. You're trying to pick the lock, but you don't realize that the cage is the only thing keeping you alive. Case #2 won't end with a 'Not Guilty.' It will end with you realizing that some doors are locked for a reason."
Nosaku turned on his heel, his red suit disappearing into the shadows of the hallway.
Arata gripped his notebook through his jacket. His hand was shaking, but not from fear. It was rage. He looked at the vial in his pocket.
"He's lying, Hana," Arata said. "The sugar didn't come from a pocket. It came from the vents. We're not going to win this in the courtroom. We're going to win this in the lab."
"Where to?" Hana asked, her voice trembling.
"We need to find the man who sold the sugar," Arata said, his eyes turning hard. "We're going to the Aichi Chiryu district. It's time to see what the 'Red Viper' is so afraid of."