Thirty floors up, a dead man lay in a sealed room. The door bolted, the windows locked. No one in. No one out. The police called it suicide. I knew better—because the killer might still be watching me.
My audit flagged the victim immediately. He was a key figure in a massive tax evasion scheme the DA's office was about to expose. This wasn't an act of desperation; it was a targeted, professional assassination meant to silence him.
The police circled the room like blind moths, obsessed with the impossibility of the locks. I wasn't.
Even in the hotel's sterile corridors, I felt the weight of unseen eyes. Whoever planned this had thought of everything—except me.
His lips were tinged blue, his skin pale but unmarked. The air in the room, thirty floors above the city noise, felt thin and cold. The autopsy confirmed a rare, rapidly dissipating asphyxiant gas—the kind used in industrial cleaning, leaving nothing behind but the color of death.
And there was one other anomaly, glinting faintly on the balcony floor: a single, half-burnt matchstick.
A single, half-burnt matchstick. The police saw a smoker's carelessness. I saw a signal. An invitation. The killer hadn't needed to break the locks; they had exploited a systemic flaw in the hotel's structure.
I ordered my team to ignore the room's layout entirely and focus on the hotel's operational data and structural schematics. My hypothesis was fixed: the killer exploited the vertical access of the building, using the matchstick as a beacon.
My team's audit of the hotel's operational schematics confirmed the necessary flaw. The adjacent rooms were useless, but the entire plan hinged on a line running thirty stories down.
The structural blueprints showed the hotel's high-speed service duct—used for window washing equipment—ran directly past the room's balcony and was only accessible from the roof level.
The analysis connected the facts with brutal simplicity:
The Assassin's Signal: The killer accessed the roof. They used the half-burnt matchstick to precisely align their position, marking the exact balcony location for their delivery system.
The Method: A transparent polymer tube, no thicker than a headphone wire, snaked down thirty stories unseen, feeding death through the small drainage gap beneath the bolted balcony door.
The Execution: The pressurized gas poison was released, killing the victim silently and instantly. The assassin simply retracted the tube.
I identified the suspect by cross-referencing the hotel's guest registry for the room directly above the victim's. The guest, who checked out immediately, was traced via a burner phone and a single financial transaction for a specialized industrial gas canister.
The perfect locked-room murder was solved through the analytical deduction of vertical access.
The killer never stepped inside the room. He didn't have to. He stood above—watching. Waiting.