The first sound was a scrape beyond the barrier, too brief to distinguish from the movement that had troubled the plates all afternoon. Mira looked up from the failed timing sheet. Across the reservoir, light ran beneath the grille and vanished in the seam. The impatient man stood at the lookout with one palm against the wall.
“There,” he said. “Someone under the broken section.”
The watcher beside the inspection case turned her head. Her partner was at the relief point, close enough to see but speaking over the noise to the person taking his place. The two of them had not completed the transfer. Mira saw the space between their attention before she understood what anyone might do with it.
“Keep the case watched,” she said.
The impatient man called again, louder. “They’re caught. I heard a voice.”
The woman beside the case moved toward the barrier. Only three steps, perhaps four, to see the place he indicated. Her partner stopped talking and followed her glance. Someone lifted the hooded lamp. Its light fell across a loose plate, a dark gap, and nothing that Mira could identify as a person.
She crossed toward them herself.
“Where?”
