From the Web he searched the Usenet – the collection of 80,000 newsgroups, in which people interested in a particular subject can post messages, pictures, programs, movies and sound clips. Gillette scoured the classic hacking newsgroups like alt.2600, alt.hack, alt.virus and alt.binaries.hacking.utilities, cutting and pasting whatever seemed relevant. He found references to dozens of newsgroups that hadn't existed when he'd gone to jail. He jumped to those groups, scrolled through them and found mention of still others.

More scrolling, more reading, more cutting and pasting.

A snap under his fingers and on the screen he saw:

mmmmmmmmmmmmmmmmmmmmmmmmmmmmm

One of his powerful keystrokes had jammed the keyboard, which had often happened when he'd been hacking. Gillette unplugged it, tossed it on the floor behind him, hooked up another keyboard and started typing again.

He then moved to the Internet Relay Chat rooms. The IRC was an unregulated no-holds-barred series of networks where you could find real-time discussions among people who had similar interests. You typed your comment, hit the ENTER key and your words appeared on the screens of everyone who was logged into the room at that time. He logged into the room #hack (the rooms were designated by a number sign followed by a descriptive word). It was in this same room where he'd spent thousands of hours, sharing information, arguing and joking with fellow hackers around the world.

After the IRC Gillette began searching through the BBS, bulletin boards, which are like Web sites but can be accessed for only the cost of a local phone call – no Internet service provider is required. Many were legitimate but many others – with names like DeathHack and Silent Spring – were the darkest parts of the online world. Completely unregulated and unmonitored, these were the places to go for recipes for bombs and poisonous gases and debilitating computer viruses that would wipe the hard drives of half the population of the world.

Following the leads – losing himself in Web sites, newsgroups, chat rooms and archives. Hunting…

This is what lawyers do when they paw through hoary old shelves searching for that one case that will save their client from execution, what sportsmen do easing through the grass toward where they thought they heard the snarl of a bear, what lovers do seeking the core of each other's lust…

Except that hunting in the Blue Nowhere isn't like searching library stacks or a field of tall grass or on your mate's smooth flesh; it's like prowling through the entire ever-expanding universe, which contains not only the known world and its unshared mysteries but worlds past and worlds yet to come.

Endless.

Snap.

He had broken another key – the all-important E. Gillette flung this keyboard into the corner of the cubicle, where it joined its dead friend.

He plugged in a new one and kept going.

At 2:30 P.M. Gillette emerged from the cubicle. His back was racked with pure fiery pain from sitting frozen in one place. Yet he could still feel the exhilarating rush from that brief time he'd spent online and the fierce reluctance at leaving the machine.

In the main part of the CCU he found Bishop talking with Shelton; the others were on telephones or standing around the white-board, looking over the evidence. Bishop noticed Gillette first and fell silent.

"I've found something," the hacker said, holding up a stack of printouts.

"Tell us."

"Dumb it down," Shelton reminded. "What's the bottom line?"

"The bottom line," Gillette responded, "is that there's somebody named Phate. And we've got a real problem."

"Fate" Frank Bishop asked.

A Gillette said. "That's his username – his screen name. Only he spells it p-h-a-t-e. Like p-h phishing, remember? The way hackers do."

It's all in the spelling…

"What's his real name?" Patricia Nolan asked.

"I don't know. Nobody seems to know much about him – he's a loner – but the people who've heard of him're scared as hell."

"A wizard?" Stephen Miller asked.

"Definitely a wizard."

Bishop asked, "Why do you think he's the killer?"

Gillette flipped through the printouts. "Here's what I found. Phate and a friend of his, somebody named Shawn, wrote some software called Trapdoor. Now, 'trapdoor' in the computer world means a hole built into a security system that lets the software designers get back inside to fix problems without needing a passcode. Phate and Shawn use the same name for their script but this's a little different. It's a program that somehow lets them get inside anybody's computer."

"Trapdoor," Bishop mused. "Like a gallows, too."

"Like a gallows," Gillette echoed.

Nolan asked, "How does it work?"

Gillette was about to explain it to her in the language of the initiated then glanced at Bishop and Shelton.

Dumb it down.

The hacker walked to one of the blank white-boards and drew a chart. He said, "The way information travels on the Net isn't like on a telephone. Everything sent online – an e-mail, music you listen to, a picture you download, the graphics on a Web site – is broken down into small fragments of data called 'packets.' When your browser requests something from a Web site it sends packets out into the Internet. At the receiving end the Web server computer reassembles your request and then sends its response – also broken into packets – back to your machine."

"Why're they broken up?" Shelton asked.

Nolan answered, "So that a lot of different messages can be sent over the same wires at the same time. Also, if some of the packets get lost or corrupted your computer gets a notice about it and resends just the problem packets. You don't have to resend the whole message."

Gillette pointed to his diagram and continued, "The packets are forwarded through the Internet by these routers – huge computers around the country that guide the packets to their final destination. Routers have real tight security but Phate's managed to crack into some of them and put a packet-sniffer inside."

"Which," Bishop said, "looks for certain packets, I assume."

"Exactly," Gillette continued. "It identifies them by somebody's screen name or the address of the machines the pack-ets're coming from or going to. When the sniffer finds the packets it's been waiting for it diverts them to Phate's computer. Once they're there Phate adds something to the packets." Gillette asked Miller, "You ever heard of stenanography?"

The cop shook his head. Tony Mott and Linda Sanchez weren't familiar with the term either but Patricia Nolan said, "That's hiding secret data in, say, pictures or sound files you're sending online. Spy stuff."

"Right," Gillette confirmed. "Encrypted data is woven right into the file itself – so that even if somebody intercepts your e-mail and reads it or looks at the picture you've sent all they'll see is an innocent-looking file and not the secret data. Well, that's what Phate's Trapdoor software does. Only it doesn't hide messages in the files – it hides an application."

"A working program?" Nolan said.

"Yep. Then he sends it on its way to the victim."

Nolan shook her head. Her pale, doughy face revealed both shock and admiration. Her voice was hushed with awe as she said, "No one's ever done that before."

"What's this software that he sends?" Bishop asked.

"It's a demon," Gillette answered, drawing a second diagram to show how Trapdoor worked.

"Demon?" Shelton asked.

"There's a whole category of software called 'bots,'" Gillette explained. "Short for 'robots.' And that's just what they are – software robots. Once they're activated they run completely on their own, without any human input. They can travel from one machine to another, they can reproduce, they can hide, they can communicate with other computers or people, they can kill themselves."