The voice came back in her ear with barely a trace of static and a slight Malaysian accent. "SQ12 on visual approach for runway two-five right. I have a U.S. Airlines Boeing 777 just clearing two-five right for the taxiway. Over."

"Roger that. The triple seven will be clear before you land. Over."

"Roger, and thanks for your help, LAX Control. We have a full load. Over."

"Welcome to LA, SQ12," Victoria signed off.

"LAX Control, this is Southwest 3567 from Albany, New York. Over."

Victoria glanced at her charts and her progress strips.

"Southwest 3567, continue your holding pattern. Expect an approach for two-five left, but we got a bunch of internationals waiting, and they're lower on fuel. Over."

"LAX Control, this is Southwest 3567. Our UAS just got triggered. Please confirm the reason for this. Over."

Victoria involuntarily looked out of the windows, scanning the sky for the plane.

"Please repeat your last, Southwest 3567. Over," she said with a sudden rasp in her voice.

"Southwest 3567 confirming activation of in-flight UAS. We have no reason to believe there are any unfriendlies on board. Please advise if you are aware of a situation. Over."

"d.a.m.n," she said. "Taylor!"

The UAS, or Uninterruptible Autopilot System, was a federal requirement in all commercial pa.s.senger jets that flew over American soil. Developed after the 9/11 attacks, it allowed ground-based flight controllers to a.s.sume control of an aircraft, flying and landing the plane using the autopilot and auto-landing system. Once activated, there was no way of retaking control from within the plane.

Taylor was at her right shoulder in a second.

"What have you got, Dean?"

"UAS on Southwest 3567 just got activated. A Boeing 787. Did we do that?"

"Not on my instruction." He spoke rapidly into a handheld radio. "Are we activating Ua.s.s on any of the planes, Simon?"

The voice sounded thin and tinny through the small speaker in the handheld. "Ah, that's a negative, Taylor. We have been instructed to avoid all computerized systems until further notice."

"Where are they?" Taylor asked, picking up a pair of binoculars off the desk.

"Southwest 3567, please confirm your course and alt.i.tude. Over," Victoria said.

The reply came immediately, and the captain's voice was calm, even curious, rather than worried. "This is Southwest 3567. We are currently pa.s.sing flight level three-two-zero and heading three-zero-zero. Where are you taking us, Control? We don't have the fuel for a long flight. Over."

"They're heading for Santa Barbara, maybe Lompoc Airport," Victoria said.

"Lompoc is a single-runway commuter airfield. They can't handle a 787," Taylor said.

"Well, after that," Victoria said, "it's straight out to sea."

"What the h.e.l.l is going on?" Taylor asked.

"We got bogeys in the wire," Dodge shouted. "Inside the building!"

"Shut it down," Jaggard said calmly. "They're all over us."

"We were the target," Vienna yelled. "Everything else was just a diversion. They were going after us all along. How the h.e.l.l did they get through our firewalls?"

"Isolate the building," Jaggard said. "Shut it down and sterilize it. Bring it back up when we're clear."

"I'm still okay," Dodge said. "I'm staying up, see if I can battle it out."

"I'm with you," Sam said. "I got infiltrated, but I saw it as it happened and blocked the intrusion before they could get a foothold."

"Don't risk it," Jaggard said. "Shut everything down, isolate the building, and we'll disinfect-" His cell phone rang, an urgent pip, pip, pip pip, pip, pip. He grabbed at it and listened intently. When he hung up, his face seemed a shade or two whiter than before.

"They're after the planes," he said. "Air traffic control in Los Angeles has just lost its flight-control systems."

"How did they get in there?" Sam asked.

"Through here," Dodge said quietly. "Once they busted us wide open, they got access to all areas. Wherever we can go, they can go."

Jaggard swore violently behind them.

"We can't shut down now," Dodge said with uncharacteristic vehemence. "By the time we get back up, this country will be a sc.r.a.p heap."

Sam concentrated on his screens. Oily black fingers dripping with poison were sliding through the network around him. He built a protective screen surrounding his and Dodge's computers, a wall of code, and lobbed fragmentation grenades over it at the intruders whenever they impinged, scrambling the data on the disk sectors they were occupying. So far it was holding.

"I want to know how they got in," Jaggard was shouting. "Who's still up?"

"I'm on it," Socks called out from across the room. "Zombie is keeping me together, just."

"Get into that firewall," Jaggard ordered. "Find out how they breached it."

"Shoot! Blue screen of death." Bashful's voice sounded to Sam's left. "I'm gone. Sorry, guys."

"Dodge, you gotta find out what they're using," Jaggard said. "I want its DNA and I want it now."

"I'm on it," Dodge said. "Shut up and let me do it."

"There's a gaping big tunnel under the firewall," Socks shouted. "That's how they got in."

"How the h.e.l.l did they get a tunnel through our firewall?" Jaggard asked. "That's supposed to be invincible!"

"It's in the firmware," Socks called back. "Looks like an exploit."

"Can't be an exploit!" Jaggard said. "Must be a bug."

"Nope, it's a trapdoor," Socks said. "It's deliberate, not bad coding."

A trapdoor in the firewall, Sam thought as he hurled a frag grenade at a murky pool of the intruder's code. How could they get a trapdoor in the firmware for the firewall?

"When was the last firmware upgrade?" Dodge asked, his eyes intent on the screen.

"Five days ago," Jaggard answered, then said, "d.a.m.n! It must be an inside job."

He punched some numbers on his cell phone and started barking commands.

"Still on the same course?" Taylor asked behind Victoria.

"I'll find out," she said, but the radio preempted her.

"LAX Control, this is Southwest 3567, advising of a course change. Turning right to nor'east six-zero."

"They're heading back inland," Taylor said. His face reflected in the inactive radar screen in front of her was grave. "Where are they going?"

Victoria plotted the course change on the chart with a pencil and a plastic ruler.

"If they stay on this course..."

"Yes?"

"San Jose," she said.

Those with fried workstations gathered around behind Dodge and Sam, watching their battle against the intruder code. The group was getting bigger. Socks was trying to revert the firmware on the firewall, but the intruders had taken control of that too. He was trying to hack back into it, so far without success.

"They want us out of the picture so they can use our access to rip through the heart of this country," Jaggard said behind them. "We're looking at a potential China Syndrome, guys, and we need some answers."

"China Syndrome" was a term that had originally come from the nuclear industry and referred to a catastrophic meltdown, supposedly a meltdown that would go all the way to China.

A meltdown of the country's computer and data infrastructure was too frightening to contemplate.

"Okay, what do we know?" Jaggard asked. "They launched a diversionary attack on a series of nuclear plants, and while we were busy with that, they opened a trapdoor in our firewall and snuck in. They're in the system and they've got control, but as long as we can keep them busy here, we can limit the damage they can do outside."

"I don't know how much longer we can hold them," Dodge said through gritted teeth. "Every time I get my hands around them, they just disappear and I'm left with a handful of dust."

"They're recoding on the fly," Sam said.

"Not possible," Dodge said. "n.o.body is that fast!"

"Tell them them that," Sam said flatly. that," Sam said flatly.

Jaggard said, "I want Cheyenne Mountain powered up now, but do not-repeat, do not-bring it online until we can confirm that the firewall there is secure. And get hold of air transport-I want all the jets fueled and sitting on the runway now. Team, we're going to move out to the backup control center at Cheyenne. We'll resume the fight from there. Dodge and Socks, you and your wingmen are going to keep them busy here. Cover the retreat. Okay, move it, people."

The group dispersed as Jaggard's cell phone rang.

"Jaggard." He listened intently for a moment, interrupting only to say, "Heading where?"

When he clicked off the phone, his face seemed pale, but he kept a professional calm.

"Everybody out, right now. Emergency evacuation procedure. That means now. And it means everybody." He was looking at Dodge and Sam.

"What is it, guv?" Dodge asked.

"Air traffic control has a 787 under remote ground control, UAS. Ninety-two pa.s.sengers, heading for San Jose. We have to a.s.sume it's under the control of the hackers."

"What?"

"I think we're the target."

Vienna's voice sounded from over by the door. "Keycard is not working. They've recoded the locks."

"What?!" Jaggard spun around toward her.

"The freaking doors are jammed," she said in a voice just teetering over into panic. "We can't get out."

21

UAS

"How long have we got?" Dodge asked calmly.

Jaggard didn't answer but pressed keys on his phone. "Put me through to LAX Control. I want the controller of that Southwest plane."

While he waited for the connection, he called out, "Leave the intruders, Socks; you're on the door codes. Find out what they did and undo it, or just find some way to open them."

"On it," Socks said.

"Dodge, you too-leave the intruders alone. Nothing we can do about them anyway. Get over to LAX and try and shut down the UAS system."

"Can't do that, guv," Dodge said. "I'm all over this guy at the moment. He's having to recode constantly to keep away from me. I take the pressure off and he'll wipe our a.r.s.es."

"You don't get over to LAX and you're going to get your a.s.s wiped by a 787," Jaggard said. He listened to his phone for a second, then pressed a key. A voice came from the overhead speakers.

"This is Victoria Dean. Who am I talking to?"

"Victoria, this is John Jaggard at Homeland Security in San Jose. We believe we may be the target of your rogue 787."

There was a short silence, and Sam thought he heard "d.a.m.n" faintly at the other end.

"Victoria, how long have we got before the plane gets here?"

Her voice came back with urgency. "You better get out of there now, sir, because he's real close."

"How close?"