Approaching thumps and rattles outside the door gave Drex hope that it might soon open. An open door, he thought, could let someone in or let someone out. Maybe both. That’s about as much planning as he had time for now. Deciding to trust his luck (which had of course gotten him into this fix in the first place), he scooped two of the smaller machines into his pants pocket and spilled the rest onto the floor. Then he positioned himself near the wall, a few feet back from the hinge side of the door.

A key slipped in the lock. Drex tensed his legs. One . . . two . . .

As soon as the steel door began to swing inward, he kicked against it with all his force. Whoever was trying to enter was thrown back hard against the door jamb. The door at once rebounded, exposing the stunned jailer. A second kick caught him in the gut, and as he crumpled Drex sprang past him and into a dim hallway. The right thing to do, he reflected, dashing for the far end of the hall, would have been to lock the guard back in his own cell.