"How can you do that if you don't know where the file is or what it's called?"

Stoll saved the blowup and exited the file, then went to Directory. He selected Library and waited while the massive list loaded.

"The photos the infiltrator used were taken before there even was an Op-Center, so this obviously took a long time to write. It's a big one. Now, it had to have come in on the coattails of some other file or we would have spotted it when we sterilize incoming software. That means the host file has to be seriously bloated."

"So we look at the file of, say, traffic light patterns in Pyongyang, and if it's thirty megabytes fat we probably have our rogue program."

"That's the drill."

"But where do we start looking? Whoever wrote the program had access to surveillance photos of North Korea-- which would make it someone at Op-Center, the NRO, the Pentagon, or ROK."

"No one at Op-Center or the NRO stands to gain by mobilization up and down the peninsula," Stoll said. "Either way, it's business as usual. Which leaves us with DOD and ROK." Stoll began running a search through the Library listing, counting the number of diskettes from each source. In order to obtain diskettes he wanted, it would be necessary to star each file and E-mail his request to Op-Center's archives; the diskettes would then be copied, hand-delivered, signed for, and erased upon their return.

"Shit," Katzen said as the number grew. "We've got about two hundred diskettes from DOD and forty-odd from ROK. It'll take days to go through them all."

After thinking for a moment, Stoll highlighted the entire ROK file.

"Starting with the shorter one?"

"No," said Stoll, "the safer one." He tapped the Star button, then Send. "If Bob Herbert ever found out I suspected our guys first, he'd kick my ass."

Katzen clapped a hand on his shoulder and rose. "I'll go bring Paul up to speed, but, Matty, I need you to do me a favor."

"Name it."

"Tell Paul that I spotted the oak."

"Okay, but why?"

"Because if our Director ever finds out that his Environmental Officer couldn't see a tree two feet in front of him, he'll kick my ass."

"Done deal," Stoll said as he sat back, folded his arms, and waited for the disks to be delivered.

CHAPTER FORTY-SIX

Tuesday, 12:30 A.M., outside of Seoul

The highways leading from Seoul to the DMZ were still crowded with military traffic, and Hwan had told his driver Cho to stick to the back roads. They followed Kim Chong's directions, a fine drizzle falling as the car headed north from the city. Cho switched on the defroster and it breathed smoothly; Hwan wished his own insides were as well tuned.

As he sat in the backseat beside Kim, Hwan wondered if this was a good idea-- ignoring the fact that for the time being, it was the only idea. Cooperating with Kim went against everything he'd been trained and raised to believe: he was going to trust a North Korean spy about matters pertaining to DPRK security. As he sat next to the young woman who gazed silently from her own window, he began having serious doubts about what he was doing. He wasn't afraid that she would try to lead him into an ambush or a nest of North Korean vipers. Hwan had made a point of sitting with his coat open, so she could see the.38 in his shoulder holster. If anything happened, she'd get a part of it. But Kim had surrendered to Bae rather than take a bullet. She wanted to live.