Far ahead, he knew, other rat robots were stationed, watching and waiting, ready to deactivate the Nipe's detection devices at just the right moment. Behind him, another horde moved forward to turn the devices on again.

It had taken a long time to learn how to shut off those detectors without giving the alarm to the Nipe's instruments.

There were nearly a hundred men in on the operation, operating the robot rats or watching the hidden cameras that spied upon the Nipe. Nearly a hundred. And all of them were safe.

They were outside the tunnel. They were with Stanton only in proxy. They could not die here in this stinking hole, but Stanton could.

There was no help for it. Stanton had to go in person. A full-sized robot proxy would be stronger, although not faster unless Stanton controlled it, than the Nipe. But the Nipe would be able to tell that it was a robot, and he would simply destroy it with one of his weapons. A remote-controlled robot would never get close enough to the Nipe to do any good.

"We do not know," Dr. Yoritomo had said, "whether he would recognize it as a robot or not, but his instruments would show the metal easily enough, and his eyes might be able to see that it was not covered with human skin. The rats are covered with real rat hides; they are small, and he is used to seeing them around. But a human-sized robot? Ah, no. Never."

So Stanton had to go in in person, walking southward, along the miles of blackness that led to the nest of the Nipe.

Overhead was Government City.

He had walked those streets only the night before, and he knew that only a short distance above him was an entirely different world.

Somewhere up there, his brother was waiting after having run the gamut of televised interviews, dinner at one of the best restaurants, and a party afterward. A celebrity. "The greatest detective in the Solar System," they'd called him. Fine stuff, that. Stanton wondered what the asteroids were like. Maybe that would be the place to go after this job was done. Maybe they'd have a place in the asteroids for a hopped-up superman.