himself stepping forward before he even thought about it. But he halted abruptly when the captain said: "There's a murderer on the loose aboard this ship. You may as well accept that fact right now. Each of you has to be on his guard. It's only right and proper that you should keep your eyes and ears open, and stay worried. If you do, our chances of catching up with him before the ship berths should be reasonably good." The captain paused, then went on quickly: "We'll get him eventually. You can be sure of that. He'll never get past the inspection each of you will have to undergo when we reach the Station. But if we catch him before we reach the Station, you'll be spared an investigative ordeal distinctly on the rugged side." Corriston was suddenly aware that he was being stared at. Everyone was staring at him. "My God!" the Captain cried out, staring the hardest of all. "Where did you get that wound? Who attacked you? And what were you doing in my cabin?" Corriston walked up to the Captain and said in a voice that trembled a little. "May I talk to you privately, sir? What I have to say won't take long." "Why not?" Sanders demanded. "That uniform you're wearing makes it mandatory. All right, come back into my cabin." They went back into the cabin. The captain shut the door and turned to face Corriston with a shocked concern in his stare. "You've had it rough, Lieutenant. I can see that." "Plenty rough," Corriston conceded. "But it's not myself I'm worried about." "Did you know that a man has just been murdered?" "I know," Corriston said. "With a poisoned barb. A Martian barb. It's a plant found only on Mars. We have him stretched out on a table in the sick bay now. But he isn't sick; he's a corpse. Tell me something, Lieutenant, did you just tangle with the man who did it?" "I think so," Corriston said. "In fact, I'd stake my commission on it." "I see. Well, you'd better tell me about it. Tell me everything." Corriston told him.