In eight months as a Sys?Sec, Phil Chartrukian had never seen TRANSLTR’s Run?Monitor post anything other than a double zero in the hours field. Today was a first.

TIME ELAPSED: 15:17:21

“Fifteen hours and seventeen minutes?” he choked. “Impossible!”

He rebooted the screen, praying it hadn’t refreshed properly. But when the monitor came back to life, it looked the same.

Chartrukian felt a chill. Crypto’s Sys?Secs had only one responsibility: Keep TRANSLTR “clean"?virus free.

Chartrukian knew that a fifteen?hour run could only mean one thing?infection. An impure file had gotten inside TRANSLTR and was corrupting the programming. Instantly his training kicked in; it no longer mattered that the Sys?Sec lab had been unmanned or the monitors switched off. He focused on the matter at hand?TRANSLTR. He immediately called up a log of all the files that had entered TRANSLTR in the last forty?eight hours. He began scanning the list.

Did an infected file get through? he wondered. Could the security filters have missed something?

As a precaution, every file entering TRANSLTR had to pass through what was known as Gauntlet?a series of powerful circuit?level gateways, packet filters, and disinfectant programs that scanned inbound files for computer viruses and potentially dangerous subroutines. Files containing programming “unknown” to Gauntlet were immediately rejected. They had to be checked by hand. Occasionally Gauntlet rejected entirely harmless files on the basis that they contained programming the filters had never seen before. In that case, the Sys?Secs did a scrupulous manual inspection, and only then, on confirmation that the file was clean, did they bypass Gauntlet’s filters and send the file into TRANSLTR.

Computer viruses were as varied as bacterial viruses. Like their physiological counterparts, computer viruses had one goal?to attach themselves to a host system and replicate. In this case, the host was TRANSLTR.

Chartrukian was amazed the NSA hadn’t had problems with viruses before. Gauntlet was a potent sentry, but still, the NSA was a bottom feeder, sucking in massive amounts of digital information from systems all over the world. Snooping data was a lot like having indiscriminate sex?protection or no protection, sooner or later you caught something.

Chartrukian finished examining the file list before him. He was now more puzzled than before. Every file checked out. Gauntlet had seen nothing out of the ordinary, which meant the file in TRANSLTR was totally clean.

“So what the hell’s taking so long?” he demanded of the empty room. Chartrukian felt himself break a sweat. He wondered if he should go disturb Strathmore with the news.

“A virus probe,” Chartrukian said firmly, trying to calm himself down. “I should run a virus probe.”

Chartrukian knew that a virus probe would be the first thing Strathmore would request anyway. Glancing out at the deserted Crypto floor, Chartrukian made his decision. He loaded the viral probe software and launched it. The run would take about fifteen minutes.

“Come back clean,” he whispered. “Squeaky clean. Tell Daddy it’s nothing.”

But Chartrukian sensed it was not “nothing.” Instinct told him something very unusual was going on inside the great decoding beast.

“Ensei Tankado is dead?” Susan felt a wave of nausea. “You killed him? I thought you said—”

“We didn’t touch him,” Strathmore assured her. “He died of a heart attack. COMINT phoned early this morning. Their computer flagged Tankado’s name in a Seville police log through Interpol.”

“Heart attack?” Susan looked doubtful. “He was thirty years old.”

“Thirty?two,” Strathmore corrected. “He had a congenital heart defect.”

“I’d never heard that.”

“Turned up in his NSA physical. Not something he bragged about.”

Susan was having trouble accepting the serendipity of the timing. “A defective heart could kill him?just like that?” It seemed too convenient.

Strathmore shrugged. “Weak heart . . . combine it with the heat of Spain. Throw in the stress of blackmailing the NSA . . .”

Susan was silent a moment. Even considering the conditions, she felt a pang of loss at the passing of such a brilliant fellow cryptographer. Strathmore’s gravelly voice interrupted her thoughts.

“The only silver lining on this whole fiasco is that Tankado was traveling alone. Chances are good his partner doesn’t know yet he’s dead. The Spanish authorities said they’d contain the information for as long as possible. We only got the call because COMINT was on the ball.” Strathmore eyed Susan closely. “I’ve got to find the partner before he finds out Tankado’s dead. That’s why I called you in. I need your help.”

Susan was confused. It seemed to her that Ensei Tankado’s timely demise had solved their entire problem. “Commander,” she argued, “if the authorities are saying he died of a heart attack, we’re off the hook; his partner will know the NSA is not responsible.”

“Not responsible?” Strathmore’s eyes widened in disbelief. “Somebody blackmails the NSA and turns up dead a few days later?and we’re not responsible? I’d bet big money Tankado’s mystery friend won’t see it that way. Whatever happened, we look guilty as hell. It could easily have been poison, a rigged autopsy, any number of things.” Strathmore paused. “What was your first reaction when I told you Tankado was dead?”

She frowned. “I thought the NSA had killed him.”

“Exactly. If the NSA can put five Rhyolite satellites in geosynchronous orbit over the Mideast, I think it’s safe to assume we have the resources to pay off a few Spanish policemen.” The commander had made his point.

Susan exhaled. Ensei Tankado is dead. The NSA will be blamed. “Can we find his partner in time?”

“I think so. We’ve got a good lead. Tankado made numerous public announcements that he was working with a partner. I think he hoped it would discourage software firms from doing him any harm or trying to steal his key. He threatened that if there was any foul play, his partner would publish the key, and all firms would suddenly find themselves in competition with free software.”

“Clever.” Susan nodded.

Strathmore went on. “A few times, in public, Tankado referred to his partner by name. He called him North Dakota.”

“North Dakota? Obviously an alias of some sort.”

“Yes, but as a precaution I ran an Internet inquiry using North Dakota as a search string. I didn’t think I’d find anything, but I turned up an E?mail account.” Strathmore paused. “Of course I assumed it wasn’t the North Dakota we were looking for, but I searched the account just to be sure. Imagine my shock when I found the account was full of E?mail from Ensei Tankado.” Strathmore raised his eyebrows. “And the messages were full of references to Digital Fortress and Tankado’s plans to blackmail the NSA.”

Susan gave Strathmore a skeptical look. She was amazed the commander was letting himself be played with so easily. “Commander,” she argued, “Tankado knows full well the NSA can snoop E?mail from the Internet; he would never use E?mail to send secret information. It’s a trap. Ensei Tankado gave you North Dakota. He knew you’d run a search. Whatever information he’s sending, he wanted you to find?it’s a false trail.”

“Good instinct,” Strathmore fired back, “except for a couple of things. I couldn’t find anything under North Dakota, so I tweaked the search string. The account I found was under a variation?NDAKOTA.”

Susan shook her head. “Running permutations is standard procedure. Tankado knew you’d try variations until you hit something. NDAKOTA’s far too easy an alteration.”

“Perhaps,” Strathmore said, scribbling words on apiece of paper and handing it to Susan. “But look at this.”

Susan read the paper. She suddenly understood the Commander’s thinking. On the paper was North Dakota’s E?mail address.