So maybe he'd been driving, Baker thought. Maybe he'd fallen asleep. Maybe his car had gone off the road and he'd had an accident. Maybe there was someone else still trapped in the car.

He heard the old guy muttering, "Left it, heft it. Go back now, get it now, and how."

Baker crossed the road to have a look. He stepped over a very large pothole, considered showing it to his wife, then decided not to.

Off the road, he didn't see any tire tracks, but he saw clearly the old man's footprints in the sand. The footprints ran back from the road into the desert. Thirty yards away, Baker saw the rim of an arroyo, a ravine cut into the landscape. The footprints seemed to come from there.

So he followed the footsteps back to the arroyo, stood at the edge, and looked down into it. There was no car. He saw nothing but a snake, slithering away from him among the rocks. He shivered.

Something white caught his eye, glinting in the sunlight a few feet down the slope. Baker scrambled down for a better look. It was a piece of white ceramic about an inch square. It looked like an electrical insulator. Baker picked it up, and was surprised to find it was cool to the touch. Maybe it was one of those new materials that didn't absorb heat.

Looking closely at the ceramic, he saw the letters ITC stamped on one edge. And there was a kind of button, recessed in the side. He wondered what would happen if he pushed the button. Standing in the heat, with big boulders all around him, he pushed it.

Nothing happened.

He pushed it again. Again nothing.

Baker climbed out of the ravine and went back to the car. The old guy was sleeping, snoring loudly. Liz was looking at the maps. "Nearest big town is Gallup."

Baker started the engine. "Gallup it is."

Back on the main highway, they made better time, heading south to Gallup. The old guy was still sleeping. Liz looked at him and said, "Dan…"