lifted an eyebrow. His athletic arms, bared by a serviceable gray tank, were shiny. “Eight,” she said.
“Nine,” he countered.
She didn’t even bother to look at him, just pushed the arrow one more time. Sweat poured down her spine in a wash, and she wiped it off her forehead. Her feet clumped hard on the rubber matting, a fact she usually hated. Tonight, the sound was lost in the heavier pounding of Scott’s tread.
The patterns whirred in her mind, and she stared into the middle distance, not seeing the white-painted cinder-block wall with its poster citing heart-rate targets, but a stream of code. Ordinarily, e-mails were a less difficult form of code to crack, because certain elements, such as headers and addresses, remained constant, and once the code could be cracked there, it fell wide open.
Not in this case. The agency had collected hundreds of e-mails over the past several weeks, as many as fifty in a single day, but in spite of their best efforts with computer algorithms and sophisticated code-breaking software, they’d made no headway.
“What…” Kim gasped, “are we…missing?”
“Network,” he growled. “Some network angle.”
Her breath was growing ragged, and her thighs were burning. She ran five to seven miles a day, as well as lifting weights and practicing kung fu for strength, but the hills were always killer. Licking salt from her upper lip, she slid a glance toward her partner to see how he was holding up.
Sweat soaked his shirt and his streaky blond hair, but Kim only needed that one glance to know he’d hit his stride. Back straight, breath heavy but even. It was easy to see him running up some forested mountain trail at ten thousand feet, his powerful body in perfect condition. Like an ad for a sport drink.
“Uncle,” she said, and pushed the arrows to bring the incline down to a more normal level.
“Thank God,” he said. “I thought it was going to be me this time.”
“Damn,” she said, and blew out a heavy breath. “One of these days, Shepherd, I am going to kick your high-altitude butt.”
“Yeah, yeah, Valenti.”
She wiped her face. As if the towel wiped away a layer of confusion, the answer to the signature was suddenly plain.
“It’s a virus,” she said.
Chapter 3
S cott wiped his face with a towel. “What is a virus?”
“That’s what the signature is, a virus mark. It’s using the virus to encode the messages, the same way a virus works to infect computers.”
“I’m not following.”
“It’s a lot more confusing to say it than it is in action. When you get a regular e-mail virus, it comes in through your e-mail program, right? Then goes out through the addresses in your address book.”
“Okay.” He lifted the towel to his mouth.
“This is working the same way. The guy writes his message, adds the signature line, and it goes through the e-mail systems, bouncing here and there and everywhere, gaining a layer of corruption—in this case, encryption—with each bounce.”
“Jeez. So how do they decode it?”
“There’s obviously a key at the other end.”
A slow grin broke on his angled face. “Let’s go find it.”
It was the break they’d been looking for. Within twelve hours, Kim and Scott had broken down the e-mails and sorted them into two piles so that they could each run decryption possibilities.
The most logical place to look was the source of the virus itself. Most encryption was “private-key,” that is, it used the same key to encrypt the message as would be used to decrypt it. While there was such a thing as “public-key” encryption, where the encoding key was different from the decoding key, it was very slow and would be too noticeable for an e-mail virus. By examining the virus, they were able to crack the code itself.
Which left another layer: the e-mails had been written in Arabic and had to be translated into English so the bulk of the messages could be read by the team.
Even then, there were missing pieces of information, but pointers clearly indicated there was trouble on the way. It looked as if it would be centered around Chicago.
“We’ve gotta call Dana,” Kim said.
“You want me to make the call?” Scott asked.
Kim gave him a glare. “No way. He can be a bastard all he likes, but he can’t stop me.”
Scott lifted a shoulder. “Why subject yourself to such a jerk? He’s old school, no point in banging your head against the wall.”
“Because dealing with me means he learns, over and over, that women are in this organization to stay.”
“Suit yourself.” He waved a file. “I’ll get this copied.”
Despite her bravado, Kim had to brace herself before she picked up the phone. Dana Milosovich was a fifty-something CIA diehard, who thought women should be secretaries, whores or wives. Not operatives. Not code breakers. He had not forgiven Kim for an incident last spring, when she’d beaten him to the draw on an important case.
Too bad.
On the other end of the line, the phone rang. “Milosovich.” His voice was as gravelly as five miles of bad road, no doubt from decades of smoking contraband Cuban cigars.
“Hello, Dana. It’s Kim Valenti, from NSA. You have a minute?”
“A short one.”
“Thanks for your graciousness.”
“Don’t mention it. What is it?”
“We’ve been following some suspicious e-mail activity related to the Q’rajn. My partner and I broke the code this morning and it appears to be pointing to plans for a terrorist attack in Chicago.”
“Yeah?”
“Looks like a bomb. Maybe a truck, something to do with the bridges over the river or a freighter on the lake. They’ve created a virus code to encrypt the e-mails, which we’ve broken, but on top of that, the cell is using another layer of code substituting one group of activities for another. We haven’t entirely sorted that part out, but we’re pretty sure the site is Chicago.”
“We’re way ahead of you, Valenti. Our operatives have been following the same cell. They’re Berzhaanian rebels, and were planning to stage an event to draw attention to the situation in their county.”
Kim scowled. “Right, but we—”
“Two key members of Q-group were killed in Berzhaan yesterday. We feel certain they’re no longer an immediate threat, and in fact recommended that Homeland Security step down to a level-yellow alert.”
“What
