Somehow, the Englishman had been downloading Trinity data into his crystal watch fob. And because no one outside Trinity's inner circle of scientists and engi¬neers knew this was even possible, Fielding could walk it in and out of the building every day without anyone suspecting a thing.

But why would he steal information? To sell to the highest bidder? Fielding was old school. Even if he were desperate for money, he was the last person I would sus¬pect of corporate espionage. Had he secretly embraced some ideology? Or abandoned one? Was he a politically naive scientist who believed all nations should share access to the latest technology? Possibly. But I didn't think he would want a rogue nation to possess some¬thing as powerful as a Trinity computer. To hear Fielding talk sometimes, you would think he didn't want any country to possess one.

Was that it? Had he been working to prevent Trinity from becoming a reality? That scenario seemed the most likely, but I didn't have enough information to make an accurate guess. And without the watch, I couldn't prove anything.

I showered in near-scalding water, then dressed in chi¬nos and a sport jacket and walked quickly to my car, try¬ing not to think too much about what I was doing. My primary goal in returning to Trinity was to find Fielding's pocket watch, but in truth I saw little choice. Staying home would only invite closer NSA scrutiny, and run¬ning-as I hoped Lu Li had done-would bring the full resources of the agency down upon me. But if I could preserve the illusion of normalcy a little longer-until the president got back to me-I might be able to avenge Fielding's death.

On a good traffic day, the Trinity complex was a twenty-minute drive from my house in suburban Chapel Hill. Research Triangle Park, the manicured haven of cor¬porate research known locally as the RTP, lay between Raleigh and Durham and was named for the triangle formed by Duke University, UNC at Chapel Hill, and North Carolina State. Its quiet lanes led through expan¬sive lawns that suggested an exclusive country club, but instead of golf links, the seven-thousand-acre RTP boasted labs owned by DuPont, 3M, Merck, Biogen, Lockheed, and dozens of other blue-chip names. Forty-five thousand people reported to work within its borders every day, but less than three hundred knew what lay behind the walls of the Trinity building. I drove slowly, hoping in some juvenile way that I would never arrive at my destination.

The Trinity lab stood two hundred yards back from an understated sign that read ARGUS OPTICAL. A forbid¬ding five-story block of steel and black glass, it sat on sixty wooded acres with extensive subbasements and a heliport. The steel and glass was just a shell constructed for show. Behind it, high-tech copper cladding code-named Tempest encased the inner building, preventing electromagnetic radiation from passing in or out of Trinity. The same stuff protected the NSA operations buildings at Fort Meade.

Because the building had been sited in a sort of bowl, its first two floors lay out of sight. The main entrance was on the third floor. To reach it, staff had to cross a roofed cat¬walk forty yards long. Inside a fortified archway at the far end, they confronted a narrow passage guarded by a security officer and lined with sensitive metal detectors, electronic bomb-sniffers, and fluoroscope machines. Authorized entry required photo ID, a fingerprint scan, and a mandatory search of all bags.

A sentry buzzed open the archway door, and I walked up to the security desk, my face revealing none of the anxiety I felt.

"Morning, Doc," said a middle-aged guard named Henry.

I sometimes thought Henry had been hired through central casting. The other security personnel were all in their late twenties, lean young men and women with smooth faces, avian eyes, and zero body fat. Only Henry, the gate man, ever said a word of greeting.

"Good morning, Henry," I said.

"There's a meeting in the conference room at nine."

"Thanks."

"You got four minutes."

I looked at my watch and nodded.

"Still can't get over Professor Fielding," Henry said. "They say he was dead before the ambulance got here."

I took a careful breath. This exchange was being recorded by hidden cameras. "That's the way it goes sometimes with strokes."

"Not a bad way to go out. Quick, I mean."

I forced a smile, then laid the pad of my right forefin¬ger on a small scanner. After the unit beeped for a match, I passed through the gauntlet of threat-detection equipment and took the stairs to the fifth floor, which housed the administrative offices and conference room.

Yellow police tape stretched across the closed door to Fielding's office. Who had put it there? Surely the NSA hadn't allowed local or state police to enter this facility. Glancing up and down the empty corridor, I quickly tried the knob. Locked. And not with some lightweight mechanism from a hardware store. If Fielding's pocket watch was inside his office, I couldn't get it.

I walked a few doors down to my own office, closed the door, and sat down at my primary computer. Part of a closed network that served only the Trinity scientists, it had no connection to the outside world. To access the Internet, I had to use a second computer that had no ports or drives through which files could be exported from the building.

My primary screen showed one interoffice e-mail: a reminder of the meeting scheduled to begin in the con¬ference room in two minutes. With a macabre chill I realized that I'd half-expected a humorous e-mail from Fielding. He often sent me little jokes or ironic quotes from dead scientists or philosophers: Scientists over 60 do more harm than good!-T. H. Huxley-like that. But today there was no message. And there would never be another. I looked blankly around my office. Fielding was gone, and I was profoundly disoriented. Together, we had stopped Project Trinity for six tense weeks, angering our colleagues while we tried in vain to discover the cause of the MRI side effects experienced by the six Trinity principals. Today that issue remained unresolved.

I hadn't volunteered to be scanned by the Super-MRI unit out of stupidity. The theory was simple: since Homo sapiens had evolved in the earth's magnetic field, an MRI's magnetic energy did not pose a health risk. This had been proved countless times by conventional MRI machines, which generated fields thirty thousand times more powerful than that of the earth. But the Super-MRI developed at Trinity-using superconductivity and colos¬sal magnets-generated fields up to eight hundred thou¬sand times greater than that of the earth. Gross side effects such as tissue-heating had been solved in animal tests, but within days after undergoing our "super-scans," all of us had begun experiencing disturbing neu¬rological symptoms.

Jutta Klein, the designer of the Super-MRI, suffered short-term memory loss. Ravi Nara endured extreme sex¬ual compulsions (he had several times been caught mas¬turbating in his office and in the rest room). John Skow developed hand tremors, and Godin himself had suffered epileptic seizures. Fielding had developed, of all things, a form of Tourette's syndrome and frequently blurted out inappropriate words or phrases. And I had narcolepsy.

Ravi Nara, our Nobel-winning neurologist, could find no medical explanation for this sudden flurry of symptoms, so all Super-MRI scanning had temporarily been halted. Work on the Trinity computer continued, but with the Super-MRI removed from the chain, Godin's engineers had only the six original scans to work from, and no one knew whether those were of suf¬ficient resolution to "make the leap" into the prototype computer. With Nara at a loss, Fielding began investigat¬ing the side effects in his spare time. Six weeks later, he suggested that they had been caused by a disruption of quantum processes in our brains-and backed up his theory with twenty pages of complex mathematics. Nara argued that nothing in the history of neuroscience sug¬gested that the human brain carried out quantum processes. Only a few physicists subscribed to this "New Age" theory of consciousness-Roger Penrose among them-yet Fielding toiled on, trying to prove his theory.