"Just checking out a suspicion, CeeCee," Matt replied lazily. "Or should I call you Cat? I've been trying to track you down ever since I saw you hit that girl at Maxim's. You've got a couple of virtual tricks I'd love to learn."

Caitlin continued to stare as if any words she might say would choke her. But she didn't get a chance to say anything.

At that moment, another blond girl, wearing an even fancier jumpsuit, came up to them. "I don't know how you got in, but if you had an invitation you'd know that proxies aren't allowed." Lara Fortune turned to Caitlin. "Friend of yours, Cat?"

"N-no," Caitlin Corrigan gulped. Her eyes still hadn't left Matt's proxy.

"I'm terribly sorry," Matt said. "I'm sure I have my invitation somewhere." He went through the motions of a man searching his pockets, which looked ridiculous on a stick figure. "Aha!" he exclaimed, pulling something out of thin air.

It wasn't an invitation icon, however. Matt shook out something that looked like a rubbery black pancake.

"What is that?" Lara Fortune demanded.

Matt tossed it to her. It landed on the front of her lace and spandex jumpsuit, creating a disgusting inky smear down the front. "It's a virtual stain. Pretty neat, huh? Or then again, maybe not."

Lara's response to the destruction of her costume was an ear-piercing scream.

For a second, Matt felt a stab of conscience at wrecking the girl's party. He'd thought maybe if he played it for laughs-but this wasn't funny. He had to keep acting as if this were fun, though.

Matt stepped back. "Maybe I should try and distract you." This time he came out with what looked like a handful of small pebbles. He turned to a nearby table, where a complicated collection of tubes created a microgravity fountain over the punch bowl. But when he tossed his handful of pebbles in, the contents of the bowl began to bubble and send up clouds of steam. Then came a muted baBOOM! A mushroom cloud of punch rose into the air and began drifting lazily downward in the low gravity. The m.u.f.fled explosion caused screams and stares. A mushroom cloud of punch rose into the air and began drifting lazily downward in the low gravity. The m.u.f.fled explosion caused screams and stares.

Cat Corrigan tried to brush off the sweet, sticky drizzle that began coming down on everybody in the room. "Yuck!" she cried as punch began soaking into her outfit and hair. But she was biting her lips to keep from laughing.

It's only a sim, Matt kept telling himself. It's not like I'm doing this in the real world It's not like I'm doing this in the real world. But a furious Lara Fortune had already whirled off to get her parents. In a second, Matt knew, automated security would be closing in on him.

"Take it easy, Cat," he said with a nonchalant wave. "By the way, nice party."

From the way Caitlin came dashing at him, Matt wondered if she were going to try tackling him to keep him there.

But all she did was yank loose one of her earrings and stuff it into his hand. "Figure it out when you're well away from here," she muttered in the midst of the chaos. "Just get out-now!"

5.

Sat.u.r.day morning, Matt asked some of his Net Force Explorer friends to make a virtual visit. They all hovered in Matt's personal veeyar, leaning over the floating marble slab/table, examining the earring Caitlin Corrigan had given Matt the night before.

"So, at least you wound up with a souvenir from your party-crashing," Andy Moore said. "You think this Senator's kid likes you?"

"That's not the point," David Gray said. "You usually can't just take off virtual bits and pieces and have them survive. This earring should have faded away when Matt cut his connection with that party. Since it didn't, we know there's more to this than meets the eye."

Silently, Matt handed over a program icon from the collection on his marble desktop-the magnifying gla.s.s.

When David held it over the earring, tiny letters sprang into being in the air-thousands of lines of them. David fiddled with the magnifying gla.s.s, making the holographic image larger, then scrolling the lines up and down.

"So," he said in satisfaction, "it's a program-a communications protocol."

"Wouldn't it have been simpler if she'd just pa.s.sed on her telephone number?" Andy asked.

"Maybe," Matt admitted. "But these are Leets we're talking about here. Rich kids. What I'm interested in is the programming, though. You guys are more up on that than I am."

Although Matt had programmed up the virtual stain he'd used on Lara Fortune's dress, he'd depended on Andy for the punch-bowl surprise. "What can you tell me?"

Both boys began scanning through the lines of programming language. "It's very good, if a bit flashy," David said. "It compresses a lot of information into such a small artifact."

"Professional," Andy added.

"Professional as in very good amateur, or is it the work of a paid program designer?" Matt asked.

"No way this could be homemade," Andy said. "There are copyright notices on some of the subroutines. This is commercial program coding-very high-end, special-designed stuff. Expensive."

"So Caitlin couldn't have written it herself?"

Andy shot him a surprised look. "I didn't know Caitlin Corrigan was a hacker."

"Neither do I," Matt said. "That's what I'm hoping to find out. Somebody had to write the coding that let the virtual vandals take over the Camden Yards computer sim system, not to mention the programming wrinkle that lets these kids hurt people in virtual realities. Let's call him-or her-the Genius. From what you're saying, I can scratch Caitlin off my list as the brains behind the vandals. She doesn't do her own programming."

Andy gave him a shrewd look. "Are you sure you're not letting her off because you like her?"

Matt could feel his face growing warm as he tried to defend himself. "I don't think so," he said.

I hope not, he thought.

"Whether she's the Genius or not, Caitlin is my connection to the other virtual vandals," Matt said. "That's what I've got to keep my attention on."

"Right." Andy gave him a wry grin. "Whatever you do, don't don't think about the fact that she wants to see you again." think about the fact that she wants to see you again."

"I could kill that idiot," Matt muttered as he sat in his room, facing his computer console.

Andy Moore had a nasty habit of dropping little bombs into a conversation that could go off minutes or even hours after he'd gone-like that little zinger about Caitlin Corrigan.

It was now early afternoon. David and Andy had left ages ago. Mom and Dad were out taking care of errands. And Matt sat staring at his computer with sightless eyes.

Just don't think about it. The words seemed to echo in his head.

An old story he'd read as a kid came out of his memory. A man suffering from a terrible illness went to the Wise Man of the Mountain to find a cure. "It is easily done," the Wise Man said. "You must go through a day without thinking of elephants."

Of course, that didn't cure the sufferer's disease. How can people spend any period of time not thinking of something they're consciously trying to avoid? The thought keeps popping up, like a pesky toothache.

Matt sighed and settled himself in his computer-link chair. He forced himself to relax, letting the chair's receivers tune into his implants. Telling the thought to go away didn't seem to be accomplishing much. Doing something was the answer.

In this case, the something would be a virtual visit to Caitlin Corrigan.

Matt opened his eyes and found himself floating in the starry twilight, facing the unsupported marble slab. In the middle was Cat's earring, right where they'd left it. Matt reached out, then suddenly pulled his hand back. Instead, he went for the glowing red p.a.w.n Leif had given him.

Glancing down, he saw he'd been reduced to a stick figure again. Only after donning the proxy disguise did Matt take up Cat's earring and the lightning-bolt teleconnection icon.

An instant later, he was flashing across the neon cityscape of the Net. Matt found himself pa.s.sing several governmental constructs. Not surprising, he thought, when you consider that Caitlin's dad is a Senator.

But suddenly, before he got too deep into government territory, the communication protocol sent him veering off. This was the equivalent of a wealthy, quiet neighborhood on the edges of the government's systems. The virtual houses were large, but not quite as self-indulgent as the vampire castles or the mansion that housed Maxim's.

Matt realized his course was taking him to a modest-looking structure with a porch and pillars. It looked strangely familiar. Then Matt recognized it. He was flying toward a simplified version of Mount Vernon, George Washington's eighteenth-century plantation house.

But he wasn't headed for a door or window. Matt was flying toward a blank wall.

A little late, he found himself remembering that Cat's gang could use virtual technology to hurt people.

Nice going, Matt thought. They could crash me out right in front of Caitlin's house. After the stunts I pulled last night, who's going to believe me when I try to explain They could crash me out right in front of Caitlin's house. After the stunts I pulled last night, who's going to believe me when I try to explain.

At the last moment, Matt jerked to a stop so sudden, it would have flung his stomach up to his throat in real life. As it was, he found himself staring at a neon-white wall.

Okay, Matt thought. Obviously I'm supposed to do something. But what? Obviously I'm supposed to do something. But what?

Cat hadn't given him a pa.s.sword. Unless...

He extended the virtual hand that held Cat's earring/doohickey. The fist sank into the wall-and so did Matt.

A moment later, he found himself in a veeyar-a perfectly flat landscape patterned like a checkerboard, vanishing off into the distance. Fluffy clouds pa.s.sed overhead, and in between, weird twisted constructs floated in midair.

Interesting, Matt thought, looking around. Lots of money went into this. He recognized one of the flying constructs as a compressed version of a very expensive virtual game. But the veeyar didn't show much in the way of programming genius. Matt's own veeyar had more personally coded touches. Most important, there was one serious lack. Caitlin Corrigan was nowhere to be seen.

Matt was just about to pull out when the girl suddenly appeared. This was a Caitlin he'd never seen before. She wore shorts and a T-shirt. Her blond hair was disheveled, held back by a terry-cloth band, and her face was sweaty.

"I was in the gym when the beeper went off," Caitlin began. Then she halted as she took in Matt's proxy figure. "Well," she said. "You're seeing me at my worst. The least you could do is drop that stupid proxy and let me know who you are."

"I'm touched that you didn't proxy up when you knew I was here," Matt replied. "But I had to work to track you down, and it's only fair that you work a little to find me."

"Who are you?" Cat burst out. "Why are you popping up around me?"

"I'm interested in you...and your friends...and what the four of you did in Camden Yards."

Caitlin's face went white. "I-I don't know what you're talking about," she stammered.

"Caitlin, Caitlin, you might like to proxy up as actresses, but you're no actress yourself. Your face just gave you away."

Caitlin bit her lip, and Matt went on. "Hey, I'm not here to arrest you. I'm a kid, not a cop. You saw what I could do at Lara's party. But what you guys can do-I'm way impressed. I'd like to meet the masters, that's all."

Cat Corrigan looked at him in silence for a long moment. Then she gave a jerky nod. "All right. I'll see what I can do. Hang here. I've got to talk to the others first."

She vanished, leaving Matt alone in her big rich kid's playground. He walked around, playing tourist, checking out the floating constructs. They were all various expensive programs, big programs, cleverly compressed for instant use.

Biggest bunch of icons I ever saw, Matt thought, a little disappointed. The whole veeyar was just a standard setup, pricey, but lacking any sense of personal involvement. Cat hadn't tried to customize it to her own personality at all.

She must be almost computer-illiterate, Matt thought. How did she get involved with the virtual vandals at all?

He became sharply aware that time was pa.s.sing. What was Caitlin doing? Had she decided to freshen up before contacting her friends? Or maybe she'd bailed out to warn them, and they were trying to decide what to do with him. Could they be trying to trace his path back through the Net? Maybe they were working to trap him in here!

Matt was on the verge of breaking contact when Caitlin returned to the veeyar. She was trying to clamp a blank expression on her face, but Matt could tell she was unhappy.

"They'll talk to you, but not here." Cat held out an icon in her hand-a little black skull.

Great, Matt thought. But he'd come too far to be scared off now. Silently, he reached out to take Caitlin's hand.

It was a short hop through the Net, quick and confusing. That was probably done on purpose, Matt figured, to make it harder for me to track them down.

They lurched wildly through several Net sites, then came to rest in an empty virtual room. The walls were so white, they almost hurt Matt's eyes.

But he wasn't paying any attention to the walls.

He was busy checking out the three proxies who stood waiting for them. They were a weird collection. The hulking, gleaming Mr. Jewels was there. So was the six-foot frog. They were accompanied by a figure that looked like an animated drawing of a cowboy.

"Mr. Dillinger, Mr. Beatty, and Dr. Crippen, I presume," Matt said, determined not to show any fear.

"Yuh know, podnuh, you been stickin' your nose in places you really shouldn't have ought," the cowboy said in the thickest Wild West accent Matt had ever heard. "Somebody ought have learned you that's dangerous."

Right then, Matt noticed that there was the barest hesitation between the cowboy's words and the movements of his lips.

But there was no slowness at all as the cowboy whipped out his cartoon pistol and pointed it at Matt's head.

"I aim to give you a good good lesson," the cowboy said. lesson," the cowboy said.

6.

Matt had seen manholes that were smaller than the muzzle of the cartoon pistol in front of his face.

"Okay, Tex, you've got my attention," he said, still determined not to give in to the fear spurting along his nerves.

These people know how to hand out pain in virtual situations, a terrified little voice chattered in the back of his head. What would it feel like to get hit by a bullet from that hand-cannon?

The giant frog suddenly changed shape, too, transforming into a rakish-looking young n.o.bleman from hundreds of years ago. Long black hair was pulled back in a ponytail, and skintight pale-leather trousers covered his legs. He wore a ruffled silk shirt-and the smile on his handsome features was as razor-sharp as the yard-long sword he aimed at Matt's throat.

And, of course, Mr. Jewels didn't need a weapon. He just loomed behind the other two, clenching gleaming fists, each as large as Matt's head.

"I really have to hand it to you guys," Matt told the threatening threesome-and the worried-looking girl. "You're good...really good. At first, I couldn't believe what I was hearing when I heard the reports about what happened in Baltimore. Then I checked out every frame of holo-imagery shot at the game, and ran a Net search to see if anything else like this had ever happened in the Washington area." good. At first, I couldn't believe what I was hearing when I heard the reports about what happened in Baltimore. Then I checked out every frame of holo-imagery shot at the game, and ran a Net search to see if anything else like this had ever happened in the Washington area."