"From what I read," Ferendelli said, "it seemed as if using molecular-size nanobots to deliver drugs directly to cancers or to specific sites in the body was still very much on the drawing boards and in the minds of futurists. I went to her to see if there was something I didn't know about the status of the field. I also needed to develop some sort of possible explanation-a hypothesis-to answer the question: If the president was being dosed with micro-amounts of psychoactive drugs, how were the chemicals being introduced into his body? How were the drugs able to seek out the area of his brain where they would be most effective? And perhaps most urgent and frightening, how could their release be triggered on cue?"

It's not in the future! Gabe wanted to shout, flashing back to the disembodied brains in Dr. Rosenberg's glass cylinders and the immunofluorescent deposits on his slides. It's here-right now! But first Gabe needed to learn how his predecessor-and Drew-had come to be in such danger.

Already it was clear to Gabe what a hero Jim Ferendelli was. In an incredibly short time, he had accumulated an astounding amount of information in trying to save the presidency of his patient and longtime friend. In the process, Jim had placed his own life in jeopardy. At this point, the man should be standing on a golden pedestal in front of Congress and the American people, awaiting the highest honors this country could bestow, not skulking in the shadows here amid the beer bottle shards and fetid odors, emaciated, unkempt, and fearful.

"What happened, Jim?" Gabe asked softly, picturing the lovingly drawn portrait in the man's desk. "What happened with Lily Sexton?"

"When I contacted Lily about picking her brain regarding nanotechnology, she invited me out to her stables for a ride. In fact, I went out there several times. It was difficult, because I had to speak to Lily in generalities, and not mention the president in any way, even though I suspected she had quickly put two and two together. We both know that my only patients are the president and his family. There have been a growing number of rumors over recent months regarding the state of Drew's mental health, and Lily's a very perceptive person."

"You'll get no argument from me there," Gabe said.

"Well, she didn't have that much to add to what I already knew about the field of nanotechnology. It's advancing at an incredible pace, and the high rollers are beginning to speculate, throwing incredible sums of money at the possibilities. But the field is still much more theoretical and potential than actual. Lily arranged for me to visit a research and manufacturing site in New Jersey and to speak with several of the scientists and even two major investors."

"Manufacturing?"

"It's a company that manufactures nanotubes of various diameters and lengths, and several different sizes of fullerenes. There's a huge demand for them right now in industries and laboratories all over the world. The people in New Jersey sell them by weight, like bananas."

"You're doing great, Jim. Can you go on?"

Ferendelli stepped out of the shadow of the bridge and scanned furtively through the gloom.

"They can kill me, Dr. Singleton," he said, a note of shrillness returning to his voice. "With the push of a button, they can kill me almost anytime they want. And they can kill the president, too. Anytime they want to they can kill him, just like that."

Gabe reached out and gently guided Ferendelli back into the darkness.

"Who are they?" he asked.

"I have some theories, but they are no more than that. I… I continued to visit Lily at her place. We never saw one another in D.C., only at Lily Pad Stables."

Gabe knew what was coming next.

"You fell in love with her, didn't you?" he said.

"I feel so stupid."

"Nonsense. I don't know if I've ever met a woman more interesting and attractive."

"Nothing ever happened between us-sexually, I mean. She kept encouraging me to visit her and ride with her, but each time I tried to advance our relationship, she alluded to being in a relationship that needed resolving before she could move on to another. Meanwhile, I kept doing research, speaking with experts, and secretly running tests on Drew's blood. I refused to believe that my relationship with Lily had no future, and she still wanted to see me. Now I know she was the one who was pumping me for information, not the other way around."

"I'm sorry, Jim," Gabe said. "I'm so sorry."

"I was a fool not to see the truth long before I did. My judgment and my ethics were warped by the feelings I had for her. I had been so lonely since my wife passed away… I…"

Gabe put his hands on the man's shoulders.

"It's okay, Jim. You did what was best for your patient. No one could ever fault you for that."

"Well, finally, in a last-ditch effort to win her over, I decided to take her into my confidence. I mean she was a friend of Drew's, and he was going to nominate her to be in his cabinet. So I told her what I had learned and what I was theorizing, and what I planned to do about it."

Again Ferendelli crossed to the edge of the bridge shadow and peered at the scene he had photographed so sensitively. The white noise and vibrations from traffic speeding overhead were in sharp contrast with the emptiness of the field and the stillness of the river. Feeling the connection between them strengthening, Gabe moved forward and stood shoulder to shoulder with his predecessor, the two of them silhouetted in the strobes of passing headlights.

"How did she respond to that?" he asked.

Ferendelli glanced over at him, his fear and sorrow nearly palpable.

"She told me I would be doing nothing of the sort-that I'd be doing exactly what she told me to do, nothing more, nothing less. She said it was in the tea she served each time before we went riding. Now it was in me-locked in place in my brain."

Gabe felt himself go numb. The tea. Lily had been so proud of her tea-so excited when he wanted another cup.

"What do you mean, it?" he asked, barely able to get the words out.

"Fullerenes-hollow nanoball molecules carrying drugs. She told me her tea was laced with just enough narcotic to make me love it, relax, and want to drink more."

"Oh, God," Gabe murmured, almost inaudibly.

"So that's how she got the fullerenes into my body. I don't know how she did it with Drew, and I don't know how the fullerenes with their microdoses of drugs end up exactly where they would have the most devastating effect."

"I'm afraid I can answer that one," Gabe said, not bothering at this point to recount his experience with the scientists in Lily's nanotech laboratory. "The fullerenes are coated with antibodies specific to neuroproteins or neurotransmitters-maybe those in the thalamus, the basal ganglia, and the caudate nucleus. Maybe other places in the brain as well. The fullerenes float through the bloodstream until they encounter those specific proteins; then they just latch on until some signal or other tells them to open up by breaking the chemical bonds that had kept them perfectly round."

"But the state of the science isn't remotely close to that level of sophisticated biotechnology," Ferendelli said.

"It is. Trust me. It is. Jim, listen, do you have any idea how the fullerenes are commanded to open?"

"Sound. They have a transmitter of some sort that must send out a specific frequency-the signal for the fullerenes to open up. Perhaps the transmitters send out different frequencies for different drugs. Lily said that chemicals had been placed in my brain stem over time and also the president's brain stem as well that could stop our heart or our breathing, or both, with just the press of a button from a transmitter. Like opening a garage door or-or changing a television channel. She actually showed one to me. Then she said I should just go about my business and nobody would be hurt-especially not the president."