He spent the rest of the day testing the theory. At the edge of the nearest eating terrace he watched the crowd gather before the evening meal and counted twelve breaths from the first soft tone to the first deep tremor under the paving. Less than half a minute later, wall panels opened and fresh trays rolled forward on silent runners. When the meal ended and people drifted away, the ground answered again with a lighter shiver, and the used vessels disappeared below.

He returned to the tower by a longer path and found another vent masked inside a bed of silver-leaf plants. This one gave off cooler air, damp with the smell of filtered water and machine oil. Beyond it, almost hidden by a folded bank of decorative stone, was a recessed patch of ground where the grass did not quite grow. The shape was oval, metal-edged under the thin soil, as if something below rose close to the surface and warmed it just enough to change what would root there.

A shaft cover, he thought. Or a service hatch hidden by landscaping.

He marked the place with the scorched composite flake he had kept in his wrap since the crash, pressing it into a crack between stones where he could find it again in low light. It was all he had to leave with certainty.

By dusk, the gardens had begun their retreat.