THIS TIME, MCGRATH did not make the tech chief come down to the third floor. He led the charge himself up to his lab on the sixth, with the videocassette in his hand. He burst in through the door and cleared a space on the nearest table. Laid the cassette in the space like it was made of solid gold. The guy hurried over and looked at it.

"I need photographs made," McGrath told him.

The guy picked up the cassette and took it across to a bank of video machines in the corner. Flicked a couple of switches. Three screens lit up with white snow.

"You tell absolutely nobody what you're seeing, OK?" McGrath said.

"OK," the guy said. "What am I looking for?"

"The last five frames," McGrath said. "That should just about cover it."

The tech chief didn't use a remote. He stabbed at buttons on the machine's own control panel. The tape rolled backward and the story of Holly Johnson's kidnap unfolded in reverse.

"Christ," he said.

He stopped on the frame showing Holly turning away from the counter. Then he inched the tape forward. He jumped Holly to the door, then face-to-face with the tall guy, then into the muzzles of the guns, then to the car. He rolled back and did it for a second time. Then a third.

"Christ," he said again.

"Don't wear the damn tape out," McGrath said. "I want big photographs of those five frames. Lots of copies."

The tech chief nodded slowly.

"I can give you laser prints right now," he said.

He punched a couple of buttons and flicked a couple of switches. Then he ducked away and booted up a computer on a desk across the room. The monitor came up with Holly leaving the dry cleaner's counter. He clicked on a couple of menus.

"OK," he said. "I'm copying it to the hard disk. As a graphics file."

He darted back to the video bank and nudged the tape forward one frame. Came back to the desk and the computer captured the image of Holly making to push open the exit door. He repeated the process three more times. Then he printed all five graphics files on the fastest laser he had. McGrath stood and caught each sheet as it flopped into the output bin.

"Not bad," he said. "I like paper better than video. Like it really exists."

The tech chief gave him a look and peered over his shoulder.

"Definition's OK," he said.

"I want blowups," McGrath told him.

"No problem, now it's in the computer," the tech said. "That's why the computer is better than paper."

He sat down and opened the fourth file. The picture of Holly and the three kidnappers in a tight knot on the sidewalk scrolled onto the screen. He clicked the mouse and pulled a tight square around the heads. Clicked again. The monitor redrew into a large blowup. The tall guy was staring straight out of the screen. The two new guys were caught at an angle, staring at Holly.

The tech hit the print button and then he opened the fifth file. He zoomed in with the mouse and put a tight rectangle around the driver, inside the car. He printed that out, too. McGrath picked up the new sheets of paper.

"Good," he said. "Good as we're going to get, anyway. Shame your damn computer can't make them all look right at the camera."

"It can," the tech chief said.

"It can?" McGrath said. "How?"

"In a manner of speaking," the guy said. He touched the blowup of Holly's face with his finger. "Suppose we wanted a face-front picture of her, right? We'd ask her to move around right in front of the camera and look right up at it. But suppose for some reason she can't move at all. What would we do? We could move the camera, right?› Suppose you climbed up on the counter and unbolted the camera off the wall and moved it down and around a certain distance until it was right in front of her. Then you'd be seeing a face-front picture, correct?"

"OK," McGrath said.

"So what we do is we calculate," the tech said. "We calculate that if we did hypothetically move that camera right in front of her, we'd have to move it what? Say six feet downward, say ten feet to the left, and turn it through about forty degrees, and then it would be plumb face-on to her. So we get those numbers and we enter them into the program and the computer will do a kind of backward simulation, and draw us a picture, just the same as if we'd really moved the actual camera right around in front of her."

"You can do that?" McGrath said. "Does it work?"

"Within its limitations," the tech chief said. He touched the image of the nearer gunman. "This guy, for instance, he's pretty much side-on. The computer will give us a full-face picture, no problem at all, but it's going to be just guessing what the other side of his face looks like, right? › It's programmed to assume the other side looks pretty much like the side it can see, with a little bit of asymmetry built in. But if the guy's got one ear missing or something, or a big scar, it can't tell us that."

"OK," McGrath said. "So what do you need?"

The chief tech picked up the wide shot of the group. Pointed here and there on it with a stubby forefinger.

"Measurements," he said. "Make them as exact as possible. I need to know the camera position relative to the doorway and the sidewalk level. I need to know the focal length of the camera lens. I need Holly's file photograph for calibration. We know exactly what she looks like, right? I can use her for a test run. I'll get it set up so she comes out right, then the other guys will come out right as well, assuming they've all got two ears and so on, like I said. And bring me a square of tile off the store's floor and one of those smocks the counter woman was wearing."

"What for?" McGrath said.

"So I can use them to decode the grays in the video," the tech said. "Then I can give you your mug shots in color."

THE COMMANDER SELECTED six women from that morning's punishment detail. He used the ones with the most demerits, because the task was going to be hard and unpleasant. He stood them at attention and drew his huge bulk up to its full height in front of them. He waited to see which of them would be the first to glance away from his face. When he was satisfied none of them dared to, he explained their duties. The blood had sprayed all over the room, hurled around by the savage centrifugal force of the blade. Chips of bone had spattered everywhere. He told them to heat water in the cookhouse and carry it over in buckets. He told them to draw scrubbing brushes and rags and disinfectant from the stores. He told them they had two hours to get the room looking pristine again. Any longer than that, they would earn more demerits.

IT TOOK TWO hours to get the data. Milosevic and Brogan went out to the dry-cleaning establishment. They closed the place down and swarmed all over it like surveyors. They drew a plan with measurements accurate to the nearest quarter-inch. They took the camera off the wall and brought it back with them. They tore up the floor and took the tiles. They took two smocks from the woman and two posters off the wall, because they thought they might help with the colorizing process. Back on the sixth floor of the Federal Building, the chief tech took another two hours to input the data. Then he ran the test, using Holly Johnson to calibrate the program.

"What do you think?" he asked McGrath.

McGrath looked hard at the full-face picture of Holly. Then he passed it around. Milosevic got it last and stared at it hardest. Covered some parts with his hand and frowned.

"Makes her look too thin," he said. "I think the bottom right quarter is wrong. Not enough width there, somehow."

"I agree," McGrath said. "Makes her jaw look weird."

The chief tech exited to a menu screen and adjusted a couple of numbers. Ran the test again. The laser printer whirred. The sheet of stiff paper came out.

"That's better," McGrath said. "Just about on the nose."

"Color OK?" the tech asked.

"Should be a darker peach," Milosevic said. "On her dress. I know that dress. Some kind of an Italian thing."

The tech exited to a color palette.

"Show me," he said.

Milosevic pointed to a particular shade.

"More like that," he said.

They ran the test again. The hard disk chattered and the laser printer whirred.

"That's better," Milosevic said. "Dress is right. Hair color is better as well."

"OK," the tech said. He saved all the parameters to disk. "Let's go to work here."

The FBI never uses latest-generation equipment. The feeling is it's better to use stuff that has been proven in the field. So the tech chief's computer was actually a little slower than the computers in the rich kids' bedrooms up and down the North Shore. But not much slower. It gave McGrath five prints within forty minutes. Four mug shots of the four kidnappers, and a close-up side view of the front half of their car. All in glowing color, all with the grain enhanced and smoothed away. McGrath thought they were the best damn pictures he had ever seen.

"Thanks, chief," he said. "These are brilliant. Best work anybody has done around here for a long time. But don't say a word. Big secret, right?"

He clapped the tech on the shoulder and left him feeling like the most important guy in the whole building.

THE SIX WOMEN worked hard and finished just before their two hours were up. The tiny cracks between the boards were their biggest problem. The cracks were tight, but not tight enough to stop the blood seeping in. But they were too tight to get a brush down in there. They had to sluice them out with water and rag them dry. The boards were turning a wet brown color. The women were praying they wouldn't warp as they dried. Two of them were throwing up. It was adding to their workload. But they finished in time for the commander's inspection. They stood rigidly at attention on the damp floor and waited. He checked everywhere, with the wet boards creaking under his bulk. But he was satisfied with their work and gave them another two hours to clean the smears off the corridor and the staircase, where the body had been dragged away.

THE CAR WAS easy. It was quickly identified as a Lexus. Four-door. Late-model. The pattern of the alloy wheel dated it exactly. Color was either black or dark gray. Impossible to be certain. The computer process was good, but not good enough to be definitive about dark automotive paint standing in bright sunshine.

"Stolen?" Milosevic said.

McGrath nodded.

"Almost certainly," he said. "You do the checking, OK?"

Fluctuations in the value of the yen had put the list price of a new Lexus four-door somewhere up there with Milosevic's annual salary, so he knew which jurisdictions were worth checking with and which weren't. He didn't bother with anywhere south of the Loop. He put in calls to the Chicago cops, and then all the departments on the North Shore right up to Lake Forest.

He got a hit just before noon. Not exactly what he was looking for. Not a stolen Lexus. But a missing Lexus. The police department in Wilmette came back to him and said a dentist up there had driven his brand-new Lexus to work, before seven on Monday morning, and parked it in the lot behind his professional building. A chiropractor from the next office suite had seen him turn into the lot. But the dentist had never made it into the building. His nurse had called his home and his wife had called the Wilmette PD. The cops had taken the report and sat on it. It wasn't the first case of a husband disappearing they'd ever heard of. They told Milosevic the guy's name was Rubin and the car was the new shade of black, mica flecks in the paint to make it sparkle, and it had vanity plates reading: ORTHO 1.

Milosevic put the phone down on that call and it rang again straightaway with a report from the Chicago Fire Department. A unit had attended an automobile fire which was putting up a cloud of oily smoke into the land-side flight path into Meigs Field Airport. The fire truck had arrived in an abandoned industrial lot just before one o'clock Monday and found a black Lexus burning fiercely. They had figured it was burned to the metal anyway, not much more smoke to come, so they had saved their foam and just left it to burn out. Milosevic copied the location and hung up. Ducked into McGrath's office for instructions.

"Check it out," McGrath told him.

Milosevic nodded. He was always happy with road work. It gave him the chance to drive his own brand-new Ford Explorer, which he liked to use in preference to one of the Bureau's clunky sedans. And the Bureau liked to let him do exactly that, because he never bothered to claim for his personal gas. So he drove the big shiny four-wheel-drive five miles south and found the wreck of the Lexus, no trouble at all. It was parked at an angle on a lumpy concrete area behind an abandoned industrial building. The tires had burned away and it was settled on the rims. The plates were still readable: ORTHO 1. He poked through the drifts of ash inside, still slightly warm, and then he pulled the shaft of the burned key from the ignition and popped the trunk. Then he staggered four steps away and threw up on the concrete. He retched and spat and sweated. He pulled his cellular phone from his pocket and fired it up. Got straight through to McGrath in the Federal Building.

"I found the dentist," he said.

"Where?" McGrath asked.

"In the damn trunk," Milosevic said. "Slow-roasted. Looks like he was alive when the fire started."

"Christ," McGrath said. "Is it connected?"

"No doubt about that," he said.

"You sure?" McGrath asked him.

"No doubt about it," Milosevic said again. "I found other stuff. Burned, but it's all pretty clear. There's a thirty-eight right in the middle of what looks like a metal hinge, could be from a woman's pocketbook, right? Coins, and a lipstick tube, and the metal parts from a mobile phone and a pager. And there are nine wire hangers on the floor. Like you get from a dry cleaner?"

"Christ," McGrath said again. "Conclusions?"

"They stole the Lexus up in Wilmette," Milosevic said.

"Maybe the dentist guy disturbed them in the act. So he went for them and they overpowered him and put him in the trunk. Burned him along with the rest of the evidence."

"Shit," McGrath said. "But where's Holly? Conclusions on that?"

"They took her to Meigs Field," Milosevic said. "It's about a half-mile away. They put her in a private plane and dumped the car right here. That's what they did, Mack. They flew her out somewhere. Four guys, capable of burning another guy up while he was still alive, they've got her alone somewhere, could be a million miles away from here by now."