The corridor outside the annex felt darker than before. Not because the day had changed much, though it had, but because he had carried a new weight back into it. He ducked under the jammed shutter and straightened too quickly. Dizziness hit. He put a hand to the outer wall and stood waiting while cool damp air touched his face.

At first the route back looked the same: broken tile, rail slot full of roots, wall lights long dead. Then the wrongness began to gather in small pieces.

A fallen panel that had blocked part of the path earlier had been shifted aside. Not far. Only enough to make a clean step-through gap. Mud at the edge of a stagnant patch showed overlapping prints—narrow, bare or soft-soled, not the wandering half-careless marks of surface dwellers. Purposeful placement. Weight carried low. A maintenance grate two meters ahead hung with one corner loose, fresh scrape marks bright against old grime.

Elias did not move for several seconds.

He turned slowly, scanning the corridor mouth, the ceiling seams, the side drains. Nothing. No visible watcher. No click signal. No breath except his own. Yet the line of changes continued when he looked for it: a vine cut cleanly where before it had sprawled across the wall seam, a cluster of loose debris nudged into an almost-arrow shape at the next split, the old civic maintenance symbol repeated in chalk so faint he might have missed it if he had not spent the whole day hunting signs.

Not random, he thought. Not chance clearing by settling or wind. Deliberate.