Desh had become stiff from his angled position in the booth as he continued to watch the entrance, and he shifted temporarily into a more comfortable position. "How can you be so sure?" he asked, rubbing the back of his neck with his left hand while continuing to grip the gun with his right.

"There are a number of ways," replied Kira. "But you'd need a much deeper knowledge of molecular biology and medicine to understand most of them. One way is to look at cellular doubling times. Most people don't know this, but most of your cells will only divide about fifty times in culture. This is called the Hayflick limit. As they approach fifty doublings they take longer and longer to divide and show signs of aging."

"What happens after they divide fifty times?" asked Desh.

"They die," she said simply.

Desh pondered this for a few seconds. "What about cancer cells?" he asked.

"Good question. Cancer cells are the exception. They're the immortals among cells. Not only will they go beyond fifty doublings, they'll continue doubling forever. It's this unconstrained growth that eventually makes them deadly to their host."

Desh was fascinated by all of this but he was out of his league and knew he needed to move on. "Let's say I believe your longevity therapy works the way you say it does," he began. "Let's say I even believe you aren't involved in bioterror. But here's the question: if you really did discover the fountain of youth, why have you kept it a secret?"

Kira raised her eyebrows. "Because I didn't want to be responsible for knocking humanity back to the Dark Ages," she said simply.

28.

David Desh spotted their waiter and motioned him over. They were in a dark, comfortable little corner of the vast mall and his fear of being discovered was waning by the minute. They had time before they had to catch the bus and he was in no hurry to leave.

"Can you start a new check for us?" asked Desh when the waiter arrived.

"Sure, what can I get for you?"

Desh quickly leafed through the menu. "We'll both have hot fudge sundaes."

The man nodded and hurried off.

"Hot fudge sundaes?" said Kira.

"I want an excuse to stay here longer," he explained. He allowed himself to smile. "Besides, when I'm talking to you my brain needs all the glucose it can get."

She looked almost bashful. "Sorry to have to throw so much at you at once. I know it's like drinking from a fire-hose."

Desh grinned at this. "Not at all. Once again you have me intrigued," he said. "So please go on."

"Smith told you his theory as to why I've kept longevity a secret," she said. "To acquire great power and wealth." She shook her head in disgust. "Nothing could be further from the truth. I'd love to share the treatment. The problem is, when I was still enhanced, I considered what the world would be like once I did. The conclusions I reached were shocking."

Desh tried to guess where she was heading, but couldn't.

"If everyone lives to be 150," continued Kira, "what happens to the world's population?"

For a moment Desh wondered if it was a trick question. He shrugged. "It would go up," he said.

"It would go up," she repeated. "A lot. At least as many people would be born each year but far fewer would die. And women would be at reproductive age twice as long. The planet is already overcrowded and getting steadily worse. Introduce my therapy and everyone would need to make room for their great, great, great grandparents." She shook her head emphatically. "Doubling the span of human life would be an absolute disaster."

"It's true our society would have to make changes," acknowledged Desh, "but you can't be sure the effects would be catastrophic."

"Overpopulation doesn't just have physical effects, it has psychological effects as well," she said. "A fascinating experiment was done on Norway rats years ago. The experimenters confined a population of them in a quarter-acre enclosure, provided plenty of food, and removed all predators. They expected the rat population to climb to 5,000, but it didn't. It stabilized at 150. When they forced the population to exceed a comfortable density, even with unlimited food, they saw a dramatic increase in pathologic rat behavior. Withdrawal, cannibalism, h.o.m.os.e.xuality, and other uncharacteristic behaviors emerged." Kira raised her eyebrows and eyed Desh knowingly. "You think human stress goes up a notch or two the more crowded it gets?"

Desh frowned. It didn't take a brilliant scientist to answer this question.

"While enhanced, I quickly realized that if I made the therapy public, the population would reach critical levels very quickly. Within a few generations, at most, humanity would either be reduced to small populations living in Dark Age conditions or extinct. I've since run a number of computer simulations."

"And?"

"And the simulations match my intuition exactly. There are a range of possible scenarios, but I'll give you one of the more likely ones. The skyrocketing population results in vast economic collapse as resources are depleted and the number of jobs can't expand as quickly as the need for them. Economies are geared to a retirement age of sixty-five or so, and an average lifespan of around eighty." Kira paused. "You even joked about the need for an immortal to have a large retirement nest egg," she reminded him.

Desh frowned. He had made the joke but had failed to consider its implications.

"We also spoke about longevity as a burden to younger generations," she continued. "It is. Along with economic collapse, population growth causes conditions to get more and more unsanitary. Contagious diseases spread like wildfire. Ma.s.sive famines become common. Fighting for survival and fueled by increases in aberrant human behavior, countries war on their international neighbors and soon unleash a nuclear Armageddon on the planet."

Desh blanched. It sounded chillingly plausible. "But wouldn't world governments realize the threat and implement strict birth-control policies?"

"Maybe. Doubtfully, but maybe. But is that what you would want? Buying increased survival at the expense of your offspring? This may sound perfectly reasonable to me when I'm enhanced, but the thought of it sickens me when I'm not." Kira paused. "There is little doubt. Springing a seventy or eighty year life extension on the world would lead to the end of civilization." She frowned and looked utterly disheartened.

The depth of despair on her face took Desh by surprise. "Kira?" he said gently, "are you okay?"

She nodded, but the sadness didn't leave her eyes. "Just feeling sorry for myself," she said softly. "My every effort blows up in my face. I can transform myself to a fantastic level of intelligence, but at the cost of becoming ruthless and losing much of my humanity. I find a way to dramatically slow the aging process, only to realize that doing so will destroy civilization."

Desh sat in silence, unable to think of anything to say. He could understand her frustration. She was a modern day Midas, the king who was thrilled to be granted a touch of gold until he realized the devastating consequences: he couldn't prevent his food or beloved daughter from turning into gold as well.

29.

They sat in silence as the waiter arrived with their desserts. Kira put a spoonful of vanilla ice-cream and hot fudge into her mouth and swallowed unhappily. Desh found himself wondering if a being of infinite intelligence would still enjoy the taste of fudge.

As Desh began working on his own sundae he decided to change the subject. Kira still had Lusetti and her brother to explain, but he was beginning to think she would. "So what happened after you realized you couldn't reveal your discovery?"

"I decided to throw in the towel. I vowed to stop all experiments on longevity and to never use my brain optimization therapy again." She waited patiently for excess fudge to finish dripping off her long spoon so she could bring it to her mouth. "But it goes without saying the story didn't end there. Someone had been keeping track of me, not with listening devices but the old fashioned way. I didn't know it at the time, but Larry Lusetti, a Private Investigator, had been hired to keep tabs on me. He went through my garbage and spied on me through my windows like a peeping tom. It didn't take long for him to discover I had stopped all experimentation."

Desh considered. "I'm guessing this signaled Moriarty that you had made a breakthrough and didn't need to experiment further."

"That's right. A few days later my condo was broken into again. I had long since stopped keeping records in a lab notebook. By then I was keeping my notes on my computer. The file was encoded and also protected by security I had devised while I was enhanced. Even if someone breached my computer, they'd have to decode the file. But a breach wasn't possible. Not by a member of h.o.m.o sapiens at any rate." She frowned deeply. "Which goes to show that just because you're smart doesn't mean you can't be incredibly stupid at the same time."

"Moriarty was able to open the file?"

She nodded. "After he broke into my condo, he must have taken one of the gellcaps that Morgan had stolen. He sat at the computer, enhanced, and was easily able to bypa.s.s my security."

Kira scowled, clearly annoyed with herself even now. "I was lucky," she continued. "I had been paranoid enough to only keep records of individual animal experiments on the computer, and philosophical musings. The actual step by step and gene by gene instructions for the longevity therapy, and for the second level of intelligence enhancement, were stored on a key-ring flash drive I kept with me at all times. There was no mention in my computer, whatsoever, that I had been working on an even greater level of intelligence enhancement. Moriarty still knows nothing about this. But I did have notes on the longevity therapy. He couldn't get the recipe, but he learned that I had found a way to extend life."

Desh's eyes narrowed. "Smith knew you had slowed the aging process by half. He also said your ultimate plan on the road to immortality was to design nan.o.bots to patrol the bloodstream, and then find a way to transfer consciousness."

"That's right. This general plan was recorded on my computer. It was my initial thinking before I realized what a disaster even the first step would be. Exactly as Smith described."

"Interesting," said Desh. "So do you think he's Moriarty?"

Kira considered. "Maybe, but my intuition tells me no. I think he's just Moriarty's lieutenant."

"Go on," said Desh, pushing his barely touched dessert to the side, having concluded that he couldn't split his focus between Kira Miller and the entrance and eat a dripping sundae at the same time.

"I knew as soon as Moriarty realized I'd discovered the fountain of youth he wouldn't rest until he had it," continued Kira. "Which meant I was in big trouble. I put the flash drive in a stainless steel pill bottle and buried it where I thought no one would ever find it. I memorized its GPS coordinates. And then I enhanced myself. I was panicked, and my thinking was scattershot, so even though I had just promised myself never to do it again, I felt I had no other choice."

Desh nodded sympathetically. Under the circ.u.mstances he couldn't blame her.

"Once I had transformed myself," she continued, "it became clear what I needed to do. The instructions for reconstructing my therapies were dozens and dozens of typed pages long. To be absolutely certain that the secret was safe, even if I was under duress, I imprisoned my memories of the formulas and the GPS coordinates to the buried flash drive: even the memory of the general area in which it was buried. I part.i.tioned these memories behind an impenetrable mental wall." She sighed. "It wasn't easy."

"I don't doubt it," said Desh.

"Even enhanced, finding and isolated specific memory traces in my own mind was an extraordinarily difficult challenge."

"But you were able to do it?"

"Yes. I structured these memories so I could only access them if I made a powerful, conscious decision that I wanted to. And like a Chinese finger trap, I set it up so the more I fought to get at the memories while under duress, the stronger the barrier would become." She paused. "As it turned out, I didn't do this a moment too soon."

Desh leaned forward intently.

"A few hours later Larry Lusetti broke into my condo and took me hostage," said Kira. "He wanted the secret to extended life and told me he wasn't leaving without it. He used truth drugs on me. They were very effective. I told him about the discovery and why I hadn't shared it with the world. But when he asked about age r.e.t.a.r.dation, I told him I didn't remember the recipe."

"Which was now absolutely true," said Desh.

Kira nodded. She took a final bite of her sundae, her spoon clinking loudly against the sides of the tall parfait gla.s.s as she retrieved it, and pushed it aside. "Unfortunately, I was unable to hold anything else back from him. Under the drugs I told him about the flash drive. I told him exactly how I had part.i.tioned the GPS coordinates in my memory so I couldn't retrieve them under duress. He dutifully reported this to Moriarty."

"And did Moriarty believe you?"

"I a.s.sume so. If not, I think he would have had Lusetti use torture in addition to truth drugs, which he never did." Kira paused as if bracing herself to continue, dreading the prospect.

Desh could sense something was very wrong. "What happened then?" he prompted gently.

"I woke up the next morning, still a hostage." She looked off into the distance and a tear slowly formed in the corner of one eye. "And Lusetti told me they had my brother, Alan."

Desh's eyes widened as the connections became obvious.

"Lusetti told me his boss was in Alan's home in Cincinnati," she whispered in horror, "and would burn my brother alive unless I gave him the secret."

"Did you?" said Desh softly.

She looked pale as she shook her head no.

Desh realized he had asked a stupid question. If Moriarty already had the fountain of youth, he wouldn't be so desperate to capture her alive.

"I knew that Moriarty was a man without principles before his brain was rewired," she explained somberly. "But if he had the secret to extended life, he could become the biggest monster in history. What could stop him? He could enhance his intelligence and could use the promise of extended life to ama.s.s power beyond imagining. The kind of power that Smith accused me of wanting."

Kira stopped and a single tear shook itself loose and rolled slowly down her cheek.

Moriarty had forced her to make an impossible decision, Desh realized. He could tell this had caused a deep rift to her psyche that would never heal. "You knew the stakes, and you did what you had to do," he said softly. "I admire you for that."

She shook her head as tears now welled up in both of her eyes. "I wasn't a hero," she said miserably. "I was a weakling. I would have done anything to save Alan, even at the risk of unleashing another Hitler on the world. I tried to unlock the memory with all of my might. But I couldn't," she whispered. "The barrier I had constructed was too good." Kira lowered her eyes. "It didn't matter, anyway. I knew in my heart that Moriarty would never let Alan go. Once I gave him what he wanted, he would kill Alan and me botha"and Lusetti as well. We would be dangerous loose ends."

Desh realized her a.n.a.lysis was dead on. She had truly been in a no win situation. "So what did you do?" he asked.

"I needed to buy time to rescue my brother. So I told Lusetti the truth. I told him I was trying but couldn't reach these memories. The software I had set up in my mind to guard them wasn't fooled. I explained I was under more duress because of the threat to my brother than if I was being physically tortured."

"Did he believe you?"

"I think so," she said, absently wiping a tear away with the back of her hand. "I pleaded with him to make sure Moriarty wouldn't hurt Alan for twenty-four hours while I found a way to unlock my memories. He told me Moriarty agreed to this."

"And then you killed Lusetti."

She nodded. "He untied me for a bathroom break right after the call with his boss. I knew I had the upper hand in any struggle. I knew he couldn't risk killing me before he had the fountain of youth. I was able to hit him with a marble bookend while he was trying to incapacitate me. I didn't want to kill him," she insisted, her voice distraught. "It just happened that way."

Desh's eyes narrowed. "So you rushed to Lusetti's apartment, hoping you could learn who was pulling his strings," he said.

"That's right. I took his laptop and a file I found with my name on it and went straight to the airport. I took the first flight to Cincinnati, using one of the false ident.i.ties I already had in place. I studied the file and laptop on the plane, but neither contained Moriarty's ident.i.ty."

Kira gathered herself. "I'm sure you've guessed the rest by now," she said. "The plane landed and I raced to my brother's house. I was determined to do whatever it took to save his life."

"But you were too late," said Desh solemnly.

A tortured expression came over Kira's face and eyes. "I was too late," she repeated softly, shuddering. She picked up a napkin and wiped away several tears that had begun to roll their way slowly down her face. "I had a special relationship with my brother Alan. He was five years older and always looked out for me. When other kids taunted me because I was different, or because I had skipped a few grades, he defended me. And then when my parents dieda""

Her voice broke. She paused and fought to get her emotions under control. "Alan was in college then," she said finally, her voice regaining strength. "At Ohio State. He took a year off to stay with me to make sure I would be okay. I pleaded with him not to put his own life on hold for me, but he wouldn't hear of it. He didn't go back to finish his degree until I left for college myself."

Desh nodded sympathetically and waited for her to continue, but her expression indicated she was emotionally spent and couldn't bear to talk about her brother any further.

"So once you realized you were too late to save him," said Desh solemnly, "you knew you had to vanish from the grid."

She nodded.

"I am truly sorry," he said softly.

Silence hung over them like a rain cloud for several long seconds.

"You killed Lusetti," said Desh finally. "But this was clearly in self defense. If what you say is true than you really haven't committed any crimes."

She sighed. "If you don't count illegal human experimentation and misappropriation of corporate resources."

"I don't," said Desh without hesitation.