"So," Anderson said, "he got inside her system from a remote location. Soft access – like we thought." He thanked the techs and they left.

Then Linda Sanchez – all business at the moment, no longer the grandmother-to-be – said to Gillette, "I've secured and logged everything in her machine." She handed him a floppy disk. "Here's a boot disk."

This was a disk that contained enough of an operating system to "boot up," or start, a suspect's computer. Police used boot disks, rather than the hard drive itself, to start the computer in case the owner – or the killer, in this case – had installed some software on the hard drive that would destroy data.

"I've been through her machine three times now and I haven't found any booby traps but that doesn't mean they aren't there. You probably know all this too but keep the victim's machine and any disks away from plastic bags or boxes or folders – they can create static and zap data. Same thing with speakers. They have magnets in them. And don't put any disks on metal shelves – they might be magnetized. You'll find nonmagnetic tools in the lab. I guess you know what to do from here."

"Yep."

She said, "Good luck. The lab's down that corridor there."

The boot disk in hand, Gillette started toward the hallway.

Bob Shelton followed.

The hacker turned. "I don't really want anybody looking over my shoulder."

Especially you, he added to himself.

"It's okay," Anderson said to the Homicide cop. "The only exit back there's alarmed and he's got his jewelry on." Nodding at the shiny metal transmission anklet. "He's not going anywhere."

Shelton wasn't pleased but he acquiesced. Gillette noticed, though, that he didn't return to the main room. He leaned against the hallway wall near the lab and crossed his arms, looking like a bouncer with a bad attitude.

If you even get an itchy look that I don't like you're going to get hurt bad…

Inside the analysis room Gillette walked up to Lara Gibson's computer. It was an unremarkable, off-the-shelf IBM clone.

He did nothing with her machine just yet, though. Instead he sat down at a workstation and wrote a kludge – a down-and-dirty software program. In five minutes he was finished writing the source code. He named the program Detective then compiled and copied it to the boot disk Sanchez had given him. He inserted the disk into the floppy drive of Lara Gibson's machine. He turned on the power switch and the drives hummed and snapped with comforting familiarity.

Wyatt Gillette's thick, muscular fingers slid eagerly onto the cool plastic of the keys. He positioned his fingertips, callused from years of keyboarding, on the tiny orientation bumps on the F and J keys. The boot disk bypassed the machine's Windows operating system and went straight to the leaner MS-DOS – the famous Microsoft Disk Operating System, which is the basis for the more user-friendly Windows. The C: prompt appeared on the black screen.

His heart raced as he stared at the hypnotically pulsing cursor.

Then, not looking at the keyboard, he pressed a key, the one for d-the first letter in the command line, detective.exe, which would start his program.

In the Blue Nowhere time is very different from what we know it to be in the Real World and, in the first thousandth of a second after Wyatt Gillette pushed that key, this happened:

The voltage flowing through the circuit beneath the d key changed ever so slightly.

The keyboard processor noticed the change in current and transmitted an interrupt signal to the computer itself, which momentarily sent the dozens of tasks it was currently performing to a storage area known as the stack and then created a special priority route for codes coming from the keyboard.

The code for the letter d was directed by the keyboard processor along this express route into the computer's basic input-output system – the BIOS – which checked to see if Wyatt Gillette had pressed the SHIFT, CONTROL or ALTERNATE keys at the same time he'd hit the d key.

Assured that he hadn't, the BIOS translated the letter's keyboard code for the lowercase d into another one, its ASCII code, which was then sent into the computer's graphics adapter.

The adapter in turn converted the code to a digital signal, which it forwarded to the electron guns located in the back of the monitor.

The guns fired a burst of energy into the chemical coating on the screen. And, miraculously, the white letter d burned into existence on the black monitor.

All this in that fraction of a second.

And in what remained of that second Gillette typed the rest of the letters of his command, e-t-e-c-t-i-v-e.e-x-e, and then hit the ENTER key with his right little finger.

More type and graphics appeared, and soon, like a surgeon on the trail of an elusive tumor, Wyatt Gillette began probing carefully through Lara Gibson's computer – the only aspect of the woman that had survived the vicious attack, that was still warm, that retained at least a few memories of who she was and what she'd done in her brief life.

He walks in a hacker's slump, Andy Anderson thought, watching Wyatt Gillette return from the analysis lab.

Machine people had the worst posture of any profession in the world.

It was nearly 11:00 A.M. The hacker had spent only thirty minutes looking over Lara Gibson's machine.

Bob Shelton, who now dogged Gillette back to the main office, to the hacker's obvious irritation, asked, "So what'd you find?" The question was delivered in a chilly tone and Anderson wondered again why Shelton was riding the young man so hard – especially considering that the hacker was helping them out on a case the detective had volunteered for.

Gillette ignored the pock-faced cop and sat down in a swivel chair, flipped open his notebook. When he spoke it was to Anderson. "There's something odd going on. The killer was in her computer. He seized root and-"

"Dumb it down," Shelton muttered. "Seized what?"

Gillette explained, "When somebody has root that means they have complete control over a computer network and all the machines on it."

Anderson added, "When you're root you can rewrite programs, delete files, add authorized users, remove them, go online as somebody else."

Gillette continued, "But I can't figure out how he did it. The only thing unusual I found were some scrambled files – I thought they were some kind of encrypted virus but they turned out to be just gibberish. There's not a trace of any kind of software on her machine that would let him get inside."

Glancing at Bishop, he explained, "See, I could load a virus in your computer that'd let me seize root on your machine and get inside it from wherever I am, whenever I want to, without needing a passcode. They're called 'back door' viruses – as in sneaking in through the back door.

"But in order for them to work I have to somehow actually install the software on your computer and activate it. I could send it to you as an attachment to an e-mail, say, and you could activate it by opening the attachment without knowing what it was. Or I could break into your house and install it on your computer then activate it myself. But there's no evidence that happened. No, he seized root some other way."

The hacker was an animated speaker, Anderson noticed. His eyes were glowing with that absorbed animation he'd seen in so many young geeks – even the ones who were sitting in court, more or less convicting themselves as they excitedly described their exploits to the judge and jury.

"Then how do you know he seized root?" Linda Sanchez asked.

"I hacked together this kludge." He handed Anderson a floppy disk.

"What's it do?" Patricia Nolan asked, her professional curiosity piqued, as was Anderson 's.