The first step into the subway tunnels felt like stepping into another world.
Lin descended last, lowering himself carefully onto the corroded service ladder. The sound of his boots hitting the damp concrete echoed down the hollow passage like a gunshot. Keller swung down ahead of him with practiced ease, grumbling as his flashlight beam flickered across rusted rails and water-stained walls. Min-joon landed unevenly, knees buckling, his breath ragged from the strain. The smell hit them next—mildew, iron, and something faintly chemical, a staleness that had clung to the tunnels ever since they'd been sealed off from the public.
"God," Min-joon muttered, covering his nose with the back of his sleeve. "It smells like rot down here."
"It's worse than rot," Keller said. His voice carried far too easily in the silence, bouncing off the curved walls. "It's stale air. Place hasn't breathed in years."
