The computer scientist hooked the shoebox-like device to the fax-machine-sized imager. He pointed the front at the building and used a button on the imager to activate the laser line scanner. This scanner would clean up the image, removing blur caused by air particles which scattered the light.

Stoll said, "Colonel, you got any idea how thick those walls are?"

"Half afoot in most places."

"Then we should be okay," Stoll said as he squatted and switched on the terahertz generator. Less than ten seconds later the device beeped. "But we'll know now for sure in half a minute."

Still squatting, Stoll leaned over and waited for the color picture to come from the imager. The paper emerged at a rate equivalent to a moderately slow fax machine. Ballon watched expectantly as the glossy sheet curled out.

When the machine stopped, Stop tore off the paper and handed it up to Ballon. The Colonel studied it in the light of a small flashlight. The others moved closer.

Hood's spirits plummeted. On the strength of this they'd be going nowhere very soon.

"What is this?" Ballon asked. "It looks like a swimming pool."

Stoll's knees popped as he rose. He looked at the image. "It's a picture of wall which is a lot thicker than six inches," he said. He studied beam-back data on the bottom of the paper. "It got 6.27 inches through the wall, then stopped. Which means it's either thicker than you thought or there's something on the other side."

Hood looked at Nancy, who was frowning. Then he looked at the five-story-tall edifice. There were windows, but they were shuttered. He was sure there would be radio-reflective materials on the other side.

Ballon threw the paper down angrily. "This is what we came here for?"

"Ya pays yer money and ya takes yer chances," Stoll said. He was obviously relieved. "I guess we should've known it wouldn't be as easy as hacking into government computers."

Even as he said it, Stoll obviously knew he'd made a mistake. Ballon turned the flashlight on him. Hood regarded the computer whiz.

"Can you break into computers?" Ballon asked.

Stoll looked at Hood. "Yes. I mean, I have. But that's highly illegal, especially--"

"We tried to get into Demain's computers," Ballon said, "but Dominique wasn't on-line anywhere we could find. I had some of our best people working on the problem."

Nancy said, "That's because you probably didn't know what you were, looking for. Did you find any of his games?"

"Of course," said Ballon.

"Then they were probably in there. Hidden inside MUDs. Multi-User Dungeons."

"Hey," said Stoll. "I was fooling around with one on the plane."

"I know," Nancy said. "I saw the commands you were typing. Also, the other message you sent."

Hood grew warm with embarrassment.