Chapter One

Hans Walther Kleinman, one of the great theoretical physicists of our time, was drowning in his bathtub. A stranger with long, sinewy arms had pinned Hans's shoulders to the porcelain bottom.

Although the water was only thirty centimeters deep, the pinioning arms kept Hans from raising his face to the surface. He clawed at the stranger's hands, trying to loosen their grip, but the man was a shtarker, a young vicious brute, and Hans was a seventy-nine-year-old with arthritis and a weak heart. Flailing about, he kicked the sides of the tub, and the lukewarm water sloshed all around him. He couldn't get a good look at his attacker -- the man's face was a shifting, watery blur. The shtarker must have slipped into the apartment through the open window by the fi re escape, then rushed into the bathroom when he realized that Hans was inside.

As Hans struggled, he felt the pressure building in his chest. It started in the center, right under his sternum, and quickly filled his whole rib cage. A negative pressure, pushing inward from all sides, constricting his lungs. Within seconds it rose to his neck, a hot choking tightness, and Hans opened his mouth, gagging. Lukewarm water rushed down his throat, and now Hans devolved into a creature of pure panic, a twisting, squirming primitive animal going into its fi nal convulsions. No, no, no, no, no, no! Then he lay still, and as his vision faded he saw only the wavelets at the surface, rippling just a few centimeters above him. A Fourier series, he thought. And so beautiful.

But it wasn't the end, not yet. When Hans regained consciousness he was lying facedown on the cold tiled fl oor, coughing up bathwater. His eyes ached and his stomach lurched and each breath was an excruciating gasp. Coming back to life was actually more painful than dying. Then he felt a sharp blow to his back, right between his shoulder blades, and heard someone say in a jaunty voice, "Time to wake up!"

The stranger grabbed him by the elbows and rolled him over. The back of Hans's head banged against the wet tiles. Still breathing hard, he looked up at his attacker, who was kneeling on the bathroom rug. A huge man, a hundred kilograms at the least. Shoulder muscles bulging under his black T-shirt, camoufl age pants tucked into black leather boots. A bald head, disproportionately small compared with his body, with black stubble on his cheeks and a gray scar on his jaw. Most likely a junkie, Hans guessed. After he kills me, he'll tear the place apart, hunting for my valuables. Only then will the stupid putz realize I don't have a goddamn cent.

The shtarker stretched his thin lips into a smile. "Now we'll have a little talk, yes? You can call me Simon, if you like."

The man's voice had an unusual accent that Hans couldn't place. His eyes were small and brown, his nose was crooked, and his skin was the color of a weathered brick. His features were ugly but indistinct -- he could be Spanish, Russian, Turkish, almost anything. Hans tried to say, "What do you want?" but when he opened his mouth he only retched again.

Simon looked amused. "Yes, yes, I'm so sorry about that. But I needed to show you that I'm serious. And better to do that right away, eh?"

Oddly enough, Hans wasn't afraid now. He'd already accepted the fact that this stranger was going to kill him. What disturbed him was the sheer impudence of the man, who kept smiling as Hans lay naked on the fl oor. It seemed clear what would happen next: Simon was going to order him to reveal the number of his ATM card. The same thing had happened to one of Hans's neighbors, an eighty-two-year-old woman who'd been attacked in her apartment and beaten until she gave up the number. No, Hans wasn't afraid -- he was furious! He coughed the last drops of bathwater out of his throat and propped himself up on his elbows. "You made a mistake this time, you ganef. I have no money. I don't even have a bank card."

"I don't want your money, Dr. Kleinman. I'm interested in physics, not money. You're familiar with the subject, I assume?"

At first Hans simply grew more enraged. Was this putz making fun of him? Who did he think he was? After a moment, though, a more disturbing question occurred to him: How did this man find out my name? And how does he know I'm a physicist?

Simon seemed to guess what Hans was thinking. "Don't be so surprised, Professor. I'm not as ignorant as I look. I may not have any advanced degrees, but I'm a fast learner."

Hans had surmised by now that this man was no junkie. "Who are you? What are you doing here?"

"Think of it as a research project. On a very challenging and esoteric topic." His smile broadened. "I admit, some of the equations weren't easy to understand. But I have some friends, you see, and they explained it very well."

"Friends? What do you mean, friends?"

"Well, perhaps that's the wrong word. Clients would probably be better. I have some very knowledgeable and well-financed clients. And they hired me to get some information from you."

"What are you talking about? Are you some kind of spy?"

Simon chuckled. "No, no, nothing so grandiose. I'm an independent contractor. Let's just leave it at that."

Hans's mind was racing now. The shtarker was a spy, or maybe a terrorist. His exact affi liation was unclear -- Iran? North Korea? Al-Qaeda? -- but that didn't matter. They were all after the same thing. What Hans didn't understand was why the bastards had targeted him of all people. Like most nuclear physicists of his generation, Hans had done some classifi ed work for the Defense Department in the fi fties and sixties, but his specialty had been radioactivity studies. He'd never worked on bomb design or fabrication, and he'd spent most of his professional life doing theoretical research that was strictly nonmilitary. "I have some bad news for your clients, whoever they are," Hans said. "They picked the wrong physicist."

Simon shook his head. "No, I don't think so."

"What kind of information do you think I can give you? Uranium enrichment? I know nothing about that! And nothing about warhead design either. My fi eld is particle physics, not nuclear engineering. All my research papers are available on the Internet, there's nothing secret about them!"

The stranger shrugged, unperturbed. "You've jumped to the wrong conclusion, I'm afraid. I don't care about warheads and I don't care about your papers. I'm interested in someone else's work, not yours."

"Why are you in my apartment, then? Did you get the wrong address?"

Simon's face hardened. He pushed Hans down on his back and placed one hand flat on his rib cage, leaning forward so he could put his whole weight on it. "This person happens to be someone you knew. Your professor at Princeton fi fty-fi ve years ago? The wandering Jew from Bavaria? The man who wrote Zur Elektrodynamik bewegter Körper? Surely you haven't forgotten him?"

Hans struggled to breathe. The shtarker's hand felt impossibly heavy. Mein Gott, he thought. This can't be happening.

Simon leaned over some more, bringing his face so close that Hans could see the black hairs inside his nostrils. "He admired you, Dr. Kleinman. He thought you were one of his most promising assistants. You worked together quite closely in his last few years, didn't you?"

Hans couldn't have replied even if he'd wanted to. Simon was pushing down on him so hard he could feel his vertebrae grinding against the cold tiles.

"Yes, he admired you. But more than that, he trusted you. He conferred with you about everything he worked on during those years. Including his Einheitliche Feldtheorie."

At just that moment one of Hans's ribs snapped. On his left side, on the outer curve, where the tensile strain was greatest. The pain knifed through his chest and Hans opened his mouth to scream, but he couldn't even draw enough breath to cry out. Oh Gott, Gott im Himmel! All at once his rational mind disintegrated, and he was afraid, he was terrified! Because he saw what this stranger wanted from him, and he knew that in the end he would be unable to resist.

Simon finally eased off and removed his hand from Hans's chest. Hans took a deep breath, and as the air whooshed in he felt the knife of pain again on his left side. His pleural membrane was torn, which meant that his left lung would soon collapse. He was weeping from the pain and shuddering with each breath. Simon stood over him with his hands on his hips, smiling contentedly, quite satisfied with his work. "So do we understand each other? Do you see what I'm looking for?"

Hans nodded, then closed his eyes. I'm sorry, Herr Doktor, he thought. I'm going to betray you now. And in his mind's eye he saw the professor again, saw him as clearly as if the great man were standing right there in the bathroom. But it was nothing like the pictures that everyone knew, the photographs of the unkempt genius with the wild white hair. What Hans remembered was the professor in the last months of his life. The drawn cheeks, the sunken eyes, the defeated grimace. The man who'd glimpsed the truth but, for the sake of the world, couldn't speak it out loud.

Hans felt a kick in his side, just below his broken rib. The pain ripped through his torso, and his eyes sprang open. One of Simon's leather boots rested on Hans's bare hip. "No time for sleeping," he said. "We have work to do. I'm going to get some paper from your desk and you're going to write everything down." He turned around and walked out of the bathroom. "If there's something I don't understand, you'll explain it to me. Like a seminar, yes? Who knows, you might even enjoy it."

Simon headed down the hallway toward Hans's bedroom. A moment later Hans heard rummaging noises. With the stranger out of sight, some of Hans's fear lifted and he was able to think again, at least until the bastard came back. And what he thought about were the shtarker's boots, his shiny black storm-trooper boots. Hans felt a wave of disgust. The man was trying to look like a Nazi. In essence, that's what he was, a Nazi, ...