Kaunas tried to smile. "What if we make a break for it while you're gone?"

"Only one of you has reason to try," said Mandel. "I think I can rely on the two innocent ones to control the third, if only out of self-protection."

He left.

It was five in the morning. Ryger looked at his watch indignantly. "A hell of a thing. I want to sleep."

"We can curl up here," said Talliaferro philosophically. "Is anyone planning a confession?"

Kaunas looked away and Ryger's lip lifted.

"I didn't think so." Talliaferro closed his eyes, leaned his large head back against the chair and said in a tired voice, "Back on the Moon, they're in the slack season. We've got a two-week night and then it's busy, busy. Then there's two weeks of sun and there's nothing but calculations, correlations and bull-sessions. That's the hard time. I hate it. If there were more women, if I could arrange something permanent-"

In a whisper, Kaunas talked about the fact that it was still impossible to get the entire Sun above the horizon and in view of the telescope on Mercury. But with another two miles of track scon to be laid down for the Observatory-move the whole thing, you know, tremendous forces involved, solar energy used directly-it might be managed. It would be managed.

Even Ryger consented to talk of Ceres after listening to the low murmur of the other voices. There was the problem there of the two-hour rotation period, which meant the stars whipped across the sky at an angular velocity twelve times that in Earth's sky. A net of three light scopes, three radio-scopes, three of everything, caught the fields of study from one another as they whirled past.

"Could you use one of the poles?" asked Kaunas.

"You're thinking of Mercury and the Sun," said Ryger impatiently. "Even at the poles, the sky would still twist, and half of it would be forever

hidden. Now if Ceres showed only one face to the Sun, the way Mercury does, we could have a permanent night sky with the stars rotating slowly once in three years."

The sky lightened and it dawned slowly.

Talliaferro was half asleep, but he kept hold of half-consciousness firmly. He would not fall asleep and leave the others awake. Each of the three, he thought, was wondering, "Who? Who?"-except the guilty one, of course.

Talliaferro's eyes snapped open as Mandel entered again. The sky, as seen from the window, had grown blue. Talliaferro was glad the window was closed. The hotel was air-conditioned, of course, but windows could be opened during the mild season of the year by those Earthmen who fancied the illusion of fresh air. Talliaferro, with Moon-vacuum on his mind, shuddered at the thought with real discomfort.

Mandel said, "Have any of you anything to say?"

They looked at him steadily. Ryger shook his head.

Mandel said, "I have developed the film in your scanners, gentlemen, and viewed the results." He tossed scanners and developed slivers of film on to the bed. "Nothing! you'll have trouble sorting out the film, I'm afraid. For that I'm sorry. And now there is still the question of the missing film."

"If any," said Ryger, and yawned prodigiously.

Mandel said, "I would suggest we come down to Villiers' room, gentlemen."

Kaunas looked startled. "Why?"

Talliaferro said, "Is this psychology? Bring the criminal to the scene of the crime and remorse will wring a confession from him?"

Mandel said, "A less melodramatic reason is that I would like to have the two of you who are innocent help me find the missing film of Villiers' paper."

"Do you think it's there?" asked Ryger challengingly.

"Possibly. It's a beginning. We can then search each of your rooms. The symposium on Astronautics doesn't start till tomorrow at 10 A.M. We have till then."

"And after that?"

"It may have to be the police."

They stepped gingerly into Villiers' room. Ryger was red, Kaunas pale. Talliaferro tried to remain calm.

Last night they had seen it under artificial lighting with a scowling, disheveled Villiers clutching his pillow, staring them down, ordering them away. Now there was the scentless odor of death about it.

Mandel fiddled with the window-polarizer to let more light in, and adjusted it too far, so that the eastern Sun slipped in.

Kaunas threw his arm up to shade his eyes and screamed, "The Sun!" so that all the others froze.

Kaunas's face showed a kind of terror, as though it were his Mercurian sun that he had caught a blinding glimpse of.

Talliaferro thought of his own reaction to the possibility of open air and his teeth gritted. They were all bent crooked by their ten years away from Earth.

Kaunas ran to the window, fumbling for the polarizer, and then the breath came out of him in a huge gasp.

Mandel stepped to his side. "What's wrong?" and the other two joined them.

The city lay stretched below them and outward to the horizon in broken stone and brick, bathed in the rising sun, with the shadowed portions toward them. Talliaferro cast it all a furtive and uneasy glance.

Kaunas, his chest seemingly contracted past the point where he could cry out, stared at something much closer. There, on the outer window sill, one corner secured in a trifling imperfection, a crack in the cement, was an inch-long strip of milky-gray film, and on it were the early rays of the rising sun.

Mandel, with an angry, incoherent cry, threw up the window and snatched it away. He shielded it in one cupped hand, staring out of hot and reddened eyes.

He said, "Wait here!"

There was nothing to say. When Mandel left, they sat down and stared stupidly at one another.

Mandel was back in twenty minutes. He said quietly (in a voice that gave the impression, somehow, that it was quiet only because its owner had passed far beyond the raving stage), "The corner in the crack wasn't overexposed. I could make out a few words. It is Villiers' paper. The rest is ruined; nothing can be salvaged. It's gone."

"What next?" said Talliaferro.

Mandel shrugged wearily. "Right now, I don't care. Mass-transference is gone until someone as brilliant as Villiers works it out again. I shall work on it but I have no illusions as to my own capacity. With it gone, I suppose you three don't matter, guilty or not. What's the difference?" His whole body seemed to have loosened and sunk into despair.

But Talliaferro's voice grew hard. "Now, hold on. In your eyes, any of the three of us might be guilty. I, for instance. You are a big man in the field and you will never have a good word to say for me. The general idea may arise that I am incompetent or worse. I will not be ruined by the shadow of guilt. Now let's solve this thing."

"I am no detective," said Mandel wearily.

"Then call in the police, damn it."

i Ryger said, "Wait a while, Tal. Are you implying that I'm guilty?" : "I'm saying that I'm innocent."

Kaunas raised his voice in fright. "It will mean the Psychic Probe for each of us. There may be mental damage-"

Mandel raised both arms high in the air. "Gentlemen! Gentlemen! Please! There is one thing we might do short of the police; and you are right, Dr. Talliaferro, it would be unfair to the innocent to leave this matter here."

They turned to him in various stages of hostility. Ryger said, "What do you suggest?"

"I have a friend named Wendell Urth. You may have heard of him, or you may not, but perhaps I can arrange to see him tonight."

"What if you can?" demanded Talliaferro. "Where does that get us?"

"He's an odd man," said Mandel hesitantly, "very odd. And very brilliant in his way. He has helped the police before this and he may be able to help us now."

PART TWO

Edward Talliaferro could not forbear staring at the room and its occupant with the greatest astonishment. It and he seemed to exist in isolation, and to be part of no recognizable world. The sounds of Earth were absent in this well-padded, windowless nest. The light and air of Earth had been blanked out in artificial illumination and conditioning.