A low tremor came up through the ground, barely enough to feel unless he locked his knees and waited for it. Then a second, a little deeper, from under the planted ridge to the west. After that came a distant clank-thrum-clank, softened by soil and structure but regular enough to count. He had heard that rhythm before without knowing he had heard it: beneath the food hall just before the wall slots opened; below the terrace where clean wraps appeared in folded stacks; under the pool court where waste vanished from hidden seams.

Not magic. Not idle ancient systems still running on grace and luck. Distribution. Lift cycles. Conveyor shifts. Service traffic.

He began to map it in his head, linking warmth, vibration, timing. The commons sat over an active network. Supplies rose where people gathered. Waste dropped where they left it. Maintenance access had to connect the tower, the halls, the transit spine, and whatever storage or machine farm kept this whole soft bright life afloat.

And because systems failed without hands, because filters clogged and bearings wore and seals broke and food did not sort itself from raw feed without oversight forever, there had to be operators. Crews. A labor force. Hidden, denied, or forgotten, but real.

The question changed shape under his feet. Not where did my machine go. Who moved it. Who moved everything.