From the corner of his eye, Logan saw Olafson turn away. “I must warn you, Jeremy — I’m afraid this part is terribly disturbing.”

Under the gaze of the camera, Logan watched Strachey move toward the wall of windows. He walked slowly at first, then more quickly and confidently. Coming up to the closest window, he tried to raise it. The heavy, old-fashioned sash rose only a few inches.

Strachey went to the next window, tugged at it with sharp, violent motions. It, too, went up just an inch or two. The old-fashioned, metal-trimmed window sashes were very heavy to begin with, Logan knew, and they probably hadn’t been cleaned and oiled in decades.

Now Strachey approached a third window; tugged again. This one rose more easily than the others had. Logan watched as Strachey pushed the sash up farther, first using both hands, then applying a shoulder. Logan could hear the grunts of effort. Finally, Strachey managed to raise the window sash to its maximum height: almost five feet above the lower sill.

There was no screen; the library was on the first floor of the building; the yawning window frame gave Strachey easy access to liberty. In another minute, he’d be through the open window and gone. What, Logan wondered, was the tragedy in one scientist gone rogue?

Except that Strachey did not go out of the window. Instead, he bent low before it, reaching in toward the right edge, fiddling with something in the groove of the frame. It was, Logan realized, the window’s sash chain. He peered in at the screen, mystified. With one hand, Strachey now held the sash chain; with the other hand, he was performing some kind of twisting motion on an object that his body blocked from view.

Then the hand pulled away. In it was an iron sash weight, about ten inches long and obviously heavy. Strachey had detached the sash weight from the window chain. He let the weight drop to the floor. His other hand still held tight to the sash chain. Only Strachey’s grasp on the chain now kept the window from crashing downward.

Suddenly, a terrible dread flooded through Logan.

Still holding tight to the chain, Strachey knelt in front of the window and rested his neck on the sill. There was a moment of stasis in which Logan, frozen in his seat, heard the man draw in several ragged breaths.

And then Strachey let go of the chain.

With a sharp screech like the whistle of a train, the heavy metal sash came hurtling down in its casing. There was a terrible crack of bone, audible even over the rattling of the window; Strachey’s body jerked as if touched by a live wire. Logan looked quickly away, but not before seeing the head go tumbling down into the flower beds outside the library, and the heavy flood of blood running dead black in the pitiless eye of the security camera.

For at least a minute, neither man moved. And then, silently, the director turned on the lights, stowed away the projector, slid the curtain back over the screen, and returned to his chair.

“My God,” Logan murmured.

“We couldn’t conceal the fact that Strachey killed himself,” Olafson said. “But for obvious reasons, we’ve tried to keep the details to a minimum. Nevertheless, rumors have been circulating.” He looked up at Logan. “I have to ask — do you have any initial thoughts?”

“My God,” Logan said again. He was in shock. He tried summoning up a mental picture of Willard Strachey from his own time at Lux, but all he could recollect was a quiet, rather shy man with thin, mouse-colored hair. They had traded smiles and nods but never a conversation.

He tried to push the shock away and address Olafson’s question. “I think,” he began slowly, “that to kill oneself in such a way…can only mean this was a man who absolutely could not bear to live another minute. He couldn’t wait until he had access to pills, a gun, a car, the roof of a building — he had to die. Immediately.”

The director nodded, leaned forward. “I don’t concern myself with the day-to-day operations of Lux; I leave that to Perry Maynard. But I knew Will Strachey for thirty years. He was the most stable, the most gentle, the most rational of men. He was also one of my best friends. He was a groomsman at my wedding. There is no way he would ever attack somebody. And he would never, ever, commit suicide — especially in such a way. Will abhorred ugliness or scenes. An act like this would be completely outside his nature.”

Olafson leaned a little closer. “The authorities, of course, just listed it as a suicide and had done. It seems they have a dim view of policy institutes and their residents to begin with. And the police psychiatrist dismissed it as, to the best of my recollection, a ‘brief reactive psychosis brought on by a fugue state.’ ” The director scoffed. “But I know that isn’t the case. And I know something else: that man in the video is not the man I knew. It’s as simple — and as mystifying — as that. And that is why we’ve asked you here.”

“It’s not exactly my line of work,” Logan said. “I’m no private detective; I’m an enigmalogist.”

“And isn’t this an enigma?” Olafson asked, passion adding a faint tremor to his voice. “I just told you — that man on the video can’t be Strachey. He would never have done such a thing. And yet there’s no denying that he killed himself. You saw him do it. I saw the body.” He paused to pass a hand across his forehead. “We need to learn what happened to him. Not for myself — but for the good of Lux.”

“You say you were one of his best friends,” Logan said. “Was there anything troubling him — anything in either his personal or professional life?”

“I didn’t see as much of him over the last year or two as I’d have liked.” Olafson waved a hand toward his desk as if pleading a heavy workload. “But I’m sure there was nothing. He never married, never minded being single. He was independently wealthy. There were no health issues — annual physicals are one of the perks here, and nothing came up at his examination two months ago; I checked. I believe he was in the process of wrapping up his work; his assistant Kim, or Dr. Maynard, could tell you more about that than I. But I can assure you the prospect of retirement didn’t concern him. Will Strachey was a full Fellow here at Lux; he’d already made a lasting contribution to his chosen area of research. He had a lot to be proud of — and he had a lot to live for. The last time we had lunch together, he spoke of all the things he was looking forward to when he retired. Touring the cathedrals of Europe — he was a huge fan of architecture and architectural design, knew a great deal about it. Picking up the piano again; did you know that he was a talented pianist, classically trained? He’d had to put his more serious instrumental studies aside years ago when his database work became all consuming. Sailing the Mediterranean — he was quite the sailor. This was a man with everything to live for. Everything.”

For almost a minute, silence descended on the office. And then, at last, Logan nodded. “One condition. I’ll need unrestricted access to Lux’s offices, labs, and records.”

The director hesitated for just a second. “Very well.”

“Am I going to need a brief? A reason to be here, poking around, asking questions? After all, there’s my, shall we say, past history with Lux to consider.”

A pained look crossed Olafson’s face. “I’ve thought about that. Many of the people you knew ten years ago are still here. And, of course, you’ve become rather well known since then. But if you’re to operate with a free hand, I don’t see how there can be any coyness or dissembling. You’re here, at the request of the board, to look into the circumstances surrounding Dr. Strachey’s death. It’s as simple as that — and I wouldn’t be any more specific.”

“Very well. Anything else I should know before I start?”