The walls were moving -- not slowly now but rapidly. They bowed out from either side between him and Tamme, compressing the hall alarmingly. "Hey!" he yelled, starting back.

Tamme had been facing away. Now she turned like an unwinding spring and ran toward him, so fast he was astonished. Her hair flew out in a straight line behind her. She approached at a good thirty miles an hour: faster than he had thought it possible for a human being on foot.

The walls accelerated. Tamme dived, angling through just as the gap closed. She landed on her hands, did a forward roll, and flipped to her feet. She came up to him, not even out of breath. "Thanks."

"That mousetrap!" he said, shaken. "It almost got you!" Then: "Thanks for what?"

"For reacting in normal human fashion. The trap was obviously geared to your capacities, not mine. That was what I needed to ascertain."

"But what was the point?"

"The object is to separate us, then deal with us at leisure. No doubt it feeds on animal flesh that it traps in this manner."

"A carnivorous world?" Veg felt an ugly gut alarm.

"Perhaps, or merely a prison, like the City. We see very little of the alternates we are visiting."

"I'm with you. Let's find the projector and get out!"

"It will have to be in a secure place -- one that the walls can not impinge on."

"Yeah. Let's stay together, huh?"

"I never intended to separate," she said. "But I wasn't sure who might be listening."

Hence the edgy tone. He'd have to be more alert next time! "You figure it's intelligent?"

"No. Mindless, perhaps purely mechanical. But dangerous -- in the fashion of a genuine mousetrap."

"Yeah -- if you happen to be the mouse."

They moved on, together. The walls were animate now, shifting like the torso of a living python. They pushed in -- but the air in the pa.s.sage compressed, preventing complete closure. There was always an exit for the air, and Veg and Tamme were able to follow it on out.

"But watch out when you see any air vent or duct," Tamme warned. "There the walls could close in all the way quite suddenly because there would be an escape for the air."

Veg became extremely interested in air vents.

Sometimes they encountered a fork in the way and had to judge quickly which branch would lead to a broader hall. But now that they understood this region's nature, they were able to stay out of trouble.

"Hey -- there it is!" he exclaimed. "The projector."

The walls were rolling back ahead of them, while closing in behind, as though herding them forward. A projector had now been revealed. It was on wheels, and a metallic ring surrounded it.

"Clever," Tamme said. "Wheels and a circular guard so that it always moves ahead of the wall and can't be trapped or crushed. So long as the walls do not close precisely parallel -- and that does not seem to be their nature -- it will squirt out. See the bearings on the ring-guard." She moved toward it.

Veg put out his hand to stop her. "Cheese," he said.

She paused. "You have a certain native cunning. I compliment you."

"Another kiss will do."

"No. I am beginning to respect you."

Veg suffered a flush of confused emotion. She did not kiss those she respected? Because a kiss decreased it -- or increased it? Or because her kisses were calculated s.e.xual attractants, not to be used on friends? Was she becoming emotionally involved? This was more the way Aquilon reacted. The notion was exciting.

"The notion is dangerous," Tamme said, reading his sentiment. "You and I are not for each other on any but the purely physical level, strictly temporary. My memory of you will be erased when I am rea.s.signed, but yours of me will remain. When emotion enters the picture, it corrupts us both. Love would destroy us."

"I'd risk it."

"You're a normal," she said with a hint of contempt. She turned to the projector. "Let's spring the mousetrap."

She brought a thread from somewhere in her uniform, then made a la.s.so. She dropped this over the switch, jerked it snug, then walked away. The thread stretched behind her, five paces, ten, fifteen.

"Hide your eyes," she said.

Veg put his arms up to cover both ears and eyes. He felt the movement as she tugged at the thread, turning on the projector.

Then he was on the floor. Tamme was picking him up. "Sorry," she said. "I miscalculated. That was an agent's trap."

"What?" He stared back down the hall, his memory coming back. There had been a terrific explosion, knocking him down --

"Directional charge. We were at the fringe of its effect. You bashed your head against the walls."

"Yeah." He felt the b.u.mp now. "Good thing that wall has some give. You people play rough."

"Yes. Unfortunately, I have been overlong on this mission. My orientation is suffering. I am making errors. A fresh agent would have antic.i.p.ated both the trap and its precise application. I regret that my degradation imperiled your well-being."

"Mistakes are only human," he said, rubbing his head.

"Precisely." She set him on his feet. "I believe the blast stunned the walls temporarily. You should be safe here while I make a quick search."

"I like you better, human."

"Misery loves company. Stay."

"Okay." He felt dizzy and somewhat nauseous. He sat down and let his head hang.

"I'm back." He had hardly been aware of her absence!

She took him to a "constant" spot she had located: six metal rods imbedded in floor and ceiling, preventing encroachment. On a pedestal within that enclosure was another projector.

"This one is safe," Tamme said.

Veg didn't ask her how she knew. Probably it was possible to b.o.o.by trap a projector to explode some time after use so that a real one could be dangerous, but that would be risky if the alternate-pattern brought the same person back again. Best not to mess with the real projectors at all! Like the way the desert Arabs never poisoned the water no matter how vicious the local politics got. Never could be sure who would need to drink next.

"I hope the next world is nicer," he said.

"Bound to be." She activated the device.