"Well, I was--" Tchassen glanced at Tynia. It would do no good, now, to explain why he had been assigned to the Nevada post. All that was finished because the station staff died in the explosion. "I wasn't on any staff," he said. "I was working on my own." "That's a pity, sir. You wouldn't remember the name of your commanding officer, then; I could have checked up on that." Tynia gasped; only then did Tchassen realize what Briggan's questions implied. He said coldly, "You're way off the track, Briggan. I'm the only one of you who couldn't be an Earthman; I haven't become acclimated yet--that's obvious, isn't it?" "Of course you're right, sir. It wouldn't be the sort of thing you could put over by playing a part, would it? Besides, Drein was the Earthman and you killed him. We've no reason to be suspicious of each other now, have we?" There was no way Tchassen could reply. He gritted his teeth and said nothing. From the expression on Tynia's face, he realized that Briggan's insinuation had been rather effective. And suppose Briggan actually believed it himself. Didn't that rule out the Sergeant as an Earthman? And it left only Tynia. Tchassen eyed the dark-haired woman on the seat beside him. What did he really know about her?--only that she had been married to a station commander; and had flirted outrageously with other post officers. She may have done it simply because she was bored; on the other hand, it could have been a deliberate attempt to create friction--exactly the sort of thing an Earth woman might try to do. Perhaps she was a native. When Tchassen was given the security assignment, he hadn't checked into her background; it didn't seem necessary. He realized suddenly that Tynia was the only witness against Drein. Because of what she had said, Tchassen had killed the Corporal. Tynia's hysteria had set the stage for murder. * * * * * As the sedan climbed higher into the pass, it moved more slowly. The motor coughed and wheezed; once or twice it seemed ready to stop altogether. When they reached the summit, the tenuous crescent of a new moon emerged above the pines. In the pale glow of light, Tchassen saw that the highway was covered with a treacherous sheet of ice. The metal rims found no traction. When the machine began to skid, the Captain found he could neither control it nor stop it. In spite of the cold, his body was covered with sweat. At a point four or five miles beyond the summit, they came to a place where thick trees on both sides of the highway shaded the road so the sun never reached it. The ice was continuous for a hundred feet or more, and it was covered with three inches of unmelted snow. The sedan skidded out of control. Tynia screamed and hid her face in her hands. Tchassen fought the wheel futilely. The car spun toward the shoulder, banged against a tree, and slid across the road into a clearing in front of an abandoned building.