Colonel Michael Gotch looked at the agent across the narrow expanse of his battered desk, then his eyes fell again to the dockets. Four dockets, four small sheaves of paper, each the capsuled story of a man's life. The names on the dockets were literally burned into his mind: Adam Philip Crag, Martin LeRoy Larkwell, Gordon Wells Nagel, Max Edward Prochaska. Four names, four men, four separate egos who, by the magic of man, had been transported to a bleak haven on another world. Four men whose task was to survive an alien hell until the U.N. officially recognized the United States' claim to sovereignty over the stark lands of the moon.

But one of the men was a saboteur, an agent whose task was to destroy the Western claim to ownership by destroying its occupancy of the moon. That would leave the East free to claim at least equal sovereignty on the basis that it, too, had established occupancy in a lunar base.

The agent broke into his thoughts. "I'd almost stake my professional reputation he's your man." He reached over and tapped one of the dockets significantly.

"The word, the single word, that's what you used to tell me to watch for. Well, the single word is there—the word that spells traitor. I'd gone over his record a dozen times before I stumbled on it." He ceased speaking and watched the Colonel.

"You may be right," Gotch said at last. "That's the kind of slip I'd pounce on myself." He hesitated.

"Go on," the agent said, as if reading his thoughts.

"There's one thing I didn't tell you because I didn't want to prejudice your thinking. The psychiatrists agree with you."

"The psychiatrists?" The agent's brow furrowed in a question.

"They've restudied the records exhaustively, ever since we first knew there was a saboteur in the crew.

"They've weighed their egos, dissected their personalities, analyzed their capabilities, literally taken them apart and put them together again. I got their report just this morning." Gotch looked speculatively at the agent. "Your suspect is also their choice. Only there is no traitor."

"No traitor?" The agent started visibly. "I don't get you."

"No traitor," Gotch echoed. "This is a tougher nut than that. The personality profile of one man shows a distinct break." He looked expectantly at the agent.

"A plant." The agent muttered, the words thoughtfully. "A ringer—a spy who has adopted the life role of another. That indicates careful planning, long preparation." He muttered the words aloud, talking to himself.

"He would have had to cover every contingency—friends, relatives, acquaintances, skills, hobbies—then, at an exact time and place, our man was whisked away and he merely stepped in." He shook his head.

"That's the kind of nut that's really tough to crack."

"Crack it," Gotch said.

The agent got to his feet "I'll dig him out," he promised savagely.

The drive to rehabilitate Red Dog became a frenzy in Crag's mind. He drove his crew mercilessly, beset by a terrible sense of urgency. Nor did he spare himself. They rigged lines in the dark of the moon and rotated the rocket on its long axis until the break in the hull was accessible.

Crag viewed it with dismay. It was far longer than he had feared—a splintered jagged hole whose raw torn edges were bent into the belly of the ship. They finally solved the problem by using the hatch door of Drone Charlie as a seal, lining it with sheets of foam from Bandit, whose interior temperature immediately plummeted to a point where it was scarcely livable.

Prochaska bore the brunt of this new discomfort. Confined as he was to the cabin and with little opportunity for physical activity, he nearly froze until he took to living in his space suit.

Crag began planning the provisioning of Red Dog even before he knew it could be repaired. During each trip from Bandit he burdened the men with supplies. Between times he managed to remove the spare oxygen cylinders carried in Drone Charlie. There was still a scant supply in Drone Baker, but he decided to leave those until later.

The problems confronting him gnawed at his mind until each small difficulty assumed giant proportions. Each time he managed to fit the work into a proper mental perspective a new problem or disaster cropped up. He grew nervous and irritable. In his frantic haste to complete the work on Red Dog he found himself begrudging the crew the few hours they took off each day for sleep. Take it easy, he finally told himself. Slow down, Adam. Yet despite his almost hourly resolves to slow down, he found himself pushing at an ever faster pace. Complete Red Dog ... complete Red Dog ... became a refrain in his mind.

Larkwell grew sullen and surly, snapping at Richter at the slightest provocation. Nagel became completely indifferent, and in the process, completely ineffectual. Crag had long realized that the oxygen man had reached his physical limits. Now, he knew, Nagel had passed them. Maybe he was right ... maybe he wouldn't leave the moon.

When the break in Red Dog was repaired, Crag waited, tense and jittery, while Nagel entered the rocket and pressurized it. It'll work, he told himself. It's got to work. The short period Nagel remained in the rocket seemed to extend into hours before he opened the hatch.

"One or two small leaks," he reported wearily. He looked disconsolately at Crag. "Maybe we can locate them—with a little time."

"Good." Crag nodded, relieved. Another crisis past. He ordered Larkwell to start pulling the engines. If things went right....

The work didn't progress nearly as fast as he had hoped. For one thing, the engines weren't designed for removal. They were welded fast against cross beams spread between the hull. Consequently, the metal sides of the ship were punctured numerous times before the job was completed. Each hole required another weld, another patch, and increased the danger of later disaster.

Crag grew steadily moodier. Larkwell seemed to take a vicious satisfaction out of each successive disaster. He had adopted an I-told-you-so attitude that grated Crag's nerves raw. Surprisingly enough, Richter proved to be a steadying influence, at least to Crag. He worked quietly, efficiently, seeming to anticipate problems and find solutions before even Crag recognized them. Despite the fact that he found himself depending on the German more and more, he was determined never to relax his surveillance over the man. Richter was an enemy—a man to be watched.

Larkwell and Nagel were lackadaisically beginning work on the ship's airlock when Prochaska came on the interphones with an emergency call.

"Gotch calling," he told Crag. "He's hot to get you on the line."

Crag hesitated. "Tell him to go to hell," he said finally. "I'll call him on the regular hour."

"He said you'd say that," Prochaska informed him amiably, "but he wants you now."

Another emergency—another hair-raiser. Gotch is a damn ulcer-maker, Crag thought savagely. "Okay, I'm on my way," he said wearily. "Anything to keep him off my back."

"Can I tell him that?"

"Tell him anything you want," Crag snapped. He debated taking the crew with him but finally decided against it. They couldn't afford the time. Reluctantly he put the work party in Larkwell's charge and started back across the bowl of the crater, each step a deliberate weighted effort. So much to do. So little time. He trudged through the night, cursing the fate that had made him Gotch's pawn.

Gotch was crisp and to the point. "Another rocket was launched from east of the Caspian this morning," he told him.

"Jesus, we need a company of Marines."

"Not this time, Adam."

"Oh ..." Crag muttered the word.

"That's right ... a warhead," Gotch confirmed.

Crag kicked the information around in his mind for a moment. "What do the computers say?"

"Too early to say for sure, but it looks like it's on the right track."

"Unless it's a direct hit it's no go. We got ten thousand foot walls rimming this hell-hole."

The Colonel was silent for a moment. "It's not quite that pat," he said finally.

"Why not?"

"Because of the low gravity. Thousands of tons of rock will be lifted. Some will escape but the majority will fall back like rain. They'll smash down over a tremendously large area, Adam. At least that's what the scientists tell us."

"Okay, in four days we'll be underground," he said with exaggerated cheerfulness, "as safe as bunnies in their burrows."

"Can you make it that fast?"

"We'll have to. That means well have to use Prochaska. That'll keep you off the lines except for the regular broadcast hour," he said with satisfaction.

Gotch snorted: "Go to hell."

"Been on the verge of it ever since we left earth."

"One other thing," Gotch said. "Baby's almost ready to try its wings."

The atomic spaceship! Crag suppressed his excitement with difficulty. He held down his voice.

"About time," he said laconically.

"Don't give me that blasÉ crap," the Colonel said cheerfully. "I know exactly how you feel." He informed him that the enemy was proclaiming to the world they had established a colony on the moon, and had formally requested the United Nations to recognize their sovereignty over the lunar world. "How's that for a stack of hogwash?" he ended.

"Pretty good," Crag agreed. "What are we claiming?"

"The same thing. Only we happen to be telling the truth."

"How will the U.N. know that?"

"We'll cross that bridge when we get to it, Adam. Just keep alive and let us worry about the U.N."

"I'm not going to commit suicide if that's what you're thinking."

"You can—if you don't keep on your toes."

"Meaning...?"

"The saboteur...." His voice fell off for a moment. "I've been wanting to talk with you about that, Adam. We have a lead. I can't name the man yet because it's pretty thin evidence. Just keep on your toes."

"I am. I'm a grown boy, remember?"

"More than usual," Gotch persisted. "The enemy is making an all-out drive to destroy Pickering Base. You can be sure the saboteur will do his share. The stage is set, Adam."

"For what?"

"For murder."

"Not this lad."

"Don't be too cocky. Remember the Blue Door episode? You're the key man ... and that makes you the key target. Without you the rest would be a cinch."

"I'll be careful," Crag promised.

"Doubly careful," Gotch cautioned. "Don't be a sitting duck. I think maybe we'll have a report for you before long," he added enigmatically.

"If the warhead doesn't get us," Crag reminded him. "And thanks for all the good news." He laughed mirthlessly. They exchanged a few more words and cut off. He turned to Prochaska, weighing his gaunt face.

"You get your wish, Max. Climb into your spaceman duds and I'll take you for a stroll. As of now you're a working man."

"Yippee," Prochaska clowned, "I've joined the international ranks of workers."

Crag's answering grin was bleak. "You'll be sorry," he said quietly.