Paul Conroe moved for the first time, running a hand through his thick gray hair as he glanced up at Schiml. "Some of that came through to me, even now," he said weakly. His face, also, was ashen and his eyes were haunted. "To think that he hated me that much, and to think why he hated me—" He shook his head and buried his face in his hands. "I never knew about the old man and the son. I just never knew. If I'd known, I'd never have done it."

The room was still for a long moment. Then Schiml blinked at Conroe, his hands trembling. "So this is the tremendous power, the mutant strain we've been trying to trace for so long."

"This is one of the tremendous powers," Conroe replied wearily. "Jeff probably has all the power that his father had, though it hasn't all matured yet. It's just latent, waiting for the time that the genes demand of his body for fulfillment. Nothing more. And other people have the same powers. Hundreds, thousands of other people. Somewhere, a hundred and fifty years ago, there was a change—a little change in one man or one woman."

He looked up at Schiml, the haunted look still in his large eyes. "Extra-sensory powers—no doubt of it, a true mutant strain, but tied in to a sleeper—a black gene that spells insanity. One became two and two spread to four—extra-sensory power and gene-linked insanity. Always together, growing, insidiously growing like a cancer. And it's eating out the roots of our civilization."

He stood up, walked across the room and stared down at the pallid-faced man in the bed. "This answers so many things, Roger," he said finally. "We knew old Jacob Meyer had a son, of course. We even suspected then that the son might share some of his powers. But this! We never dreamed it. The father and son were practically two people with one mind, in almost perfect mutual rapport. Only the son was so young he couldn't understand what was wrong. All he knew was that he 'felt' Daddy and could tell what Daddy was thinking. Actually, everything that went on in his father's mind—everything—was in his mind too. At least, in the peak of the old man's cycle of insanity—"

Schiml looked up sharply. "Then there's no doubt in your mind that the old man was insane?"

Conroe shook his head. "Oh, no. There was no doubt. He was insane, all right. A psychiatric analysis of his behavior was enough to convince me of that, even if following him and watching him wasn't. He had a regular cycle of elation and depression, so regular it could almost be clocked. He'd even spotted the symptoms of the psychosis himself, back in his college days. But of course he hadn't realized what it was. All he knew was that at certain times he seemed to be surrounded by these peculiar phenomena, which happened rapidly and regularly at those times when he was feeling elated, on top of the world. And at other times he seemed to carry with him an aura of depression. Actually, when he hit the blackest depths of his depressions, he would be bringing about whole waves of suicides and depression—errors and everything else."

Conroe took a deep breath. "We knew all this at the time, of course. What we didn't know was that the old man had been seeking the answer himself, actively seeking it. All we knew was that he was actively the most dangerous man alive on Earth, and that until he was killed he would become more and more dangerous—dangerous enough to shake the very roots of our civilization."

Schiml nodded slowly. "And you're sure that his destructive use of his power was a result directly of the insanity?"

Conroe frowned. "Not quite," he said after a moment. "Actually, you couldn't say that Jacob Meyer 'used' his extra-sensory powers. They weren't, for the most part, the kind of powers he could either control or 'use.' They were the sort of powers that just happened. He had a power, and when he was running high—in a period of elation, when everything was on top of the world—the power functioned. He fairly exuded this power that he carried, and the higher he rose in his elation, the more viciously dangerous the power became."

Conroe stopped, staring at the bed for a long moment. "The hellish thing was that it couldn't possibly be connected up with a human power at all. After all, how can one human being have an overwhelming effect on the progress of a business cycle? He can't, of course, unless he's a dictator, or a tremendously powerful person in some other field. And Jacob Meyer was neither. He was a simple, half-starved statistician with a bunch of ideas that he couldn't even understand himself, much less sell to anyone who could do anything with them. Or how can a man, just by being in the vicinity, tip the balance that topples the stock market into an almost irreparable sag?"

Conroe leaned forward, groping for words. "Jacob Meyer's psychokinesis was not the sort of telekinesis that we saw Jeff turning against me in that room a couple of hours ago. He could probably have managed that, too, if he had hated me enough. But if Jacob Meyer's mind had merely affected physical things—the turn of a card, the fall of the dice, the movement of molecules from one place to another—he would have been a simple problem. We could have isolated him, studied him. But it wasn't that simple."

Paul Conroe sat back, regarding Schiml with large, sad eyes. "It would have been impossible to prove in a court of law. We knew it and the government knew it. That was why they appointed us assassins to deal with him. Because Jacob Meyer's mind affected probabilities. By his very presence, in a period of elation, he upset the normal probabilities of occurrences going on around him. We watched him, Roger. It was incredible. We watched him in the stock market, and we saw the panic start almost the moment he walked in. We saw the buyers suddenly and inexplicably change their minds and start selling instead of buying. We saw what happened in the Bank of the Metropolis that first day we tried for him. He was scared, his mind was driven into a peak of fear and anger; it started a bank run that morning that nearly bankrupted the most powerful financial house on the East Coast! We saw this one little man's personal, individual influence on international diplomacy, on finances, on gambling in Reno, on the thinking and acting of the man on the street. It was incredible, Roger."

"But surely Jacob Meyer wasn't the only one—"

"Oh, there were others, certainly. We've a better idea of that, now, after all these years of study. There were and are thousands and thousands—some like me, some much worse—all carrying some degree of extra-sensory power from that original mutant strain, all with the gene-linked psychosis paired up with it every time. And we've seen our civilization struggling against these thousands just to keep its feet. But Jacob Meyer was the first case of the whole, full-blown change in one man that we'd ever found. He was running wild, his mind was completely insane. And the extra-sensory powers he carried were so firmly enmeshed in the insanity that there was no separating the two. Meyer tipped us off. He set us on the trail, and the trail led to his son after he was dead—"

"Yes, the son. We have the son." Schiml scowled at the shallow-breathing form on the bed. "We should have had him before—years before."

"Of course we should. But the son vanished after his father's death. We never knew why he vanished—until now. But now we know that when we killed his father, we did more than just that. We almost killed our last chance to catch this thing and study it before it was too late. Because when we killed Jeff's father, we killed Jeff Meyer too."

Schiml scowled. "I don't follow. He's still alive."

"Oh, of course he's still alive. But can't you see what happened to him? He was living in his father's mind; he knew everything his father knew—but he didn't understand it. He thought with his father's thoughts, he saw through his father's eyes, because they were mutually and completely telepathic. He felt his father's fear and frustration and bitterness when we trapped him in that office building finally. He lay screaming on the ground on a farm somewhere, but actually he was in his father's mind.

"It was a mad mind, a mind rising to the highest screaming heights of mania, as he waited for me to come down and kill him. And Jeff was surrounded with his father's hatred. He saw my face through his father's eyes, and all he could understand was that his daddy was being butchered and that I was butchering him. When the bullet went into his father's brain and split his skull open, Jeff Meyer felt that too. When his father died, Jeff died too—a part of him, that is. They were one mind and part of that one mind was destroyed."

Conroe paused, his forehead covered with perspiration. The room was silent except for the hoarse breathing of the man on the table. Conroe's face, as he looked down, was that of a ghost.

"No wonder the boy disappeared," he whispered. "He'd been shot through the head. He was almost virtually dead. He must have gone into shock for years after such a trauma, Roger. He must have spent years roaming that farm, cared for by an aunt or uncle or cousin, while he slowly recovered. No wonder we could find no trace. And then, when he did get well, all he knew was that his father had been murdered. He didn't know how; he didn't know why, and he dared never remember the truth. Because, the truth was that he had been killed. All he dared recognize was my face—a recurrent, nightmarish hallucination, rising out of his dreams, plaguing him on the streets, tormenting him day and night."

"But you were hunting him."

"Oh, yes, we were hunting him. It was inevitable that sooner or later we would come up face to face. But when we did, I received such a horrible mental blow that I couldn't even look to see what he looked like. I could do nothing but scream and run. When he saw me that day in the night club, he took complete leave of his senses. He exploded into hatred and bitterness. And then he resolved to hunt me down and kill me for killing his father."

Conroe spread his hands apologetically. "It seemed good sense to use that hatred and singleness of purpose to draw him here. But it was torture. He followed me with his mind, without even knowing it. It was old Jacob Meyer's face that haunted me everywhere I went. I didn't know why, then, because I didn't know Jeff had been part of that mind. And Jeff didn't know that he carried and broadcast that horror wherever he went."

Conroe leaned back, his body limp in exhaustion. "We needed Jeff so desperately. Yes, we needed him in here, for testing, for this study. It's been a long, tedious job, studying him, observing him, photographing him, learning how much of his father's power he had. And we dared not bring him in here until we were sure it was safe. And now, with what he knows, he is more vitally dangerous than his father ever was. There are hundreds that carry the change, in larger or smaller part, all gene-linked with insanity. And Jeff Meyer is insane as any of the rest of them. But at least there's hope, because we can study him now. Because unless we can somehow separate the function of the insanity from the function of the psychokinesis, we have no choice left, no hope."

Schiml looked up, his eyes wide. "No choice—"

"—but to kill them, every one. To hunt out the strain and wipe it from the face of the Earth so ruthlessly and completely that it can never rise again. And to wipe out with it the first new link in the evolution of Man since the dawn of history."

Slowly Roger Schiml's eyes traveled from Jeff Meyers' form on the bed to Paul Conroe's grave face. "There's no other way?"

"None," said Paul Conroe.

"Jeff," said Dr. Schiml. "Jeff Meyer."

The figure on the cot stirred ever so slightly. The eyes slowly closed, then reopened, looking slightly less blank. Jeff's lips parted in an almost inaudible groan, hardly more than a breath.

"Jeff. You've got to hear me a minute. Listen, Jeff, we're trying to help you. Can you hear that? We're trying to help you, Jeff, and we need your help."

The eyes shifted, turned to Schiml's face. They were haunted eyes—eyes that had seen the grave and beyond it.

"Please, Jeff. Listen. We're hunting. We're trying to find a way to help you. You know about your father now, the truth about your father, don't you?"

The eyes wavered, came back, and the head nodded ever so slightly. "I know," came the sighing reply.

"You've got to tell us what to do, Jeff. There are good powers here in your mind, and there are terrible powers, ruinous powers. We've got to find them both, find where they lie, how they work. You must tell us, as we probe—tell us when we strike the good, when we strike the bad. Do you understand, Jeff?"

Again the head nodded. Jeff's jaw tightened a trifle and an expression of infinite fatigue crossed his face. "Go on, Doc."

Dr. Schiml leaned over the proper controls and moved the dial on the microvernier. He moved it again, watching, moving it still again. A fine sweat broke out on his forehead as he worked, and he felt Conroe's soft eyes on him, waiting, hoping....

And then a whimper broke from Jeff's lips, an indefinable sound, helpless and childlike, a little cry of terror. Dr. Schiml looked up, his heart thumping in his throat. Jeff's eyes were wide again, staring lifelessly, and his breath was shallow and thready. Schiml glanced quickly at Conroe, then back, his eyes reflecting the fear and tension in his mind. And as he worked his shoulders slumped forward, prepared for defeat. Because what he was doing was impossible, and he knew it was impossible. But he knew, above all, that it had to succeed.