"Bert—"

"You said that before."

"Bert, listen!" screeched Gaines.

Sokolski looked up at the high ceiling, squinted, and tried to place the perfectly familiar but unidentifiable sound that came whispering down the maze.

And then he knew. "The door to the pile!" he spluttered.

Gaines was beside himself with horror. "Bert, let's get going. I don't like this—"

All of a sudden Geiger counters in the room began their deadly conversation, a rising argument that swooped in seconds from a low mumble to a shouting thunder-storm of sound. Gamma signals hooted, the tip off cubes on either side of the maze entrance became red, and the radiation tabs clipped to their wrists turned color before their eyes.

Then they were staring for what seemed like an eternity, utterly overwhelmed by its very impossibility, at a sight they had never imagined they might ever see: a pile servomech wheeling silently around the last bend in the maze and straight toward them.

Sokolski had sense enough to push the red emergency button as they fled past it.