The route had been prepared for him. He could see that much even in the weak red strips sunk into the wall seams. A reflective bit of foil tucked at an angle. Above it, a maintenance grate sat a finger's width off true, with fresh scratches bright on one hinge as if someone had used it recently and fast. A smear of white chalk at knee height where the shaft met a narrow service throat. Someone had wanted him to find this entrance. That did not mean they had wanted him alive at the other end.

He crouched when he stepped off the ladder because the ceiling dropped suddenly. Water ticked from a pipe joint into a gutter cut through the floor. The passage ran left and right between bundled conduits wrapped in old insulation. He took out the pale chip of broken tile and scratched a quick mark beside the chalk, an old habit from field surveys, then went left where the foil caught the little light.

His plan, such as it was, had seemed almost respectable above ground. Follow the guided descent. Confirm traffic. Identify an access route toward the archive or tower support levels. Do not engage unless forced. Return with proof. It lasted less than three minutes.

A sound clicked in the dark ahead. Another answered behind him.

Elias stopped. Not machine. Not random pipe strike. Deliberate spacing.