Carter had been injured in a reactor explosion aboard the Starship _Alpha Centauri_, where he had been navigator. He came out of that pretty lightly--radiation burns, a fractured skull, and little other damage. Some skin grafts and a complicated titanium-plate rebuild had his body and his skull as good as new within weeks. He was on his way to Ophiuchus to rest up before returning to spaceline duty. But his flight was interrupted when his detectors picked up an SOS as he passed the Deneb system. "SOS! SOS! General rescue call!" It was coming over on a wide-beam cast. Carter localized it on Deneb IV, an unexplored world, and replied, "I hear you. Who's this?" "Survey Ship _Vanguard_. We're in trouble." "How many are you?" "Twelve, altogether. Urgent that you rescue us." Carter glanced around his small ship. Its maximum capacity was fifteen; he could just about make it. "I'll be right down," he said. "Give me landing coordinates." They read off a string of figures and he computed an orbit. Minutes later, he had set his ship down in the exact spot they had selected, only to find the planet bare of life and no Earthmen in sight. He had looked around, puzzled. Then the rangy spaceman had struck him from behind. And now, Carter was following his captive through a wild, untamed jungle, heading into some strange mystery at whose nature he could only guess. The titanium plate in his skull was beginning to itch faintly as he moved deeper and deeper into the jungle. After a while, signs of inhabitation began to appear. Carter spotted the golden hull of a spaceship towering above the trees, and touched his guide's arm. "Is that the _Vanguard_?" "Yes." Behind the ship, Carter could now see a large clearing, and people moving around in it, clad in the uniform of the Survey Division of the Intergalactic Federation. There was a building in the background, square and dull-gray. A man stepped forward to meet them. He was distinguished-looking and wore the uniform of a Squadron Leader. "I'm Gendron," he said. "Commander of the _Vanguard_." "The name's Dave Carter, navigator, late of Starship _Alpha Centauri_. I picked up your SOS call." Gendron blinked. "SOS? What SOS?" "The one you sent out, of course," Carter replied, astonished. "I've got it on tape back at my ship. You asked for immediate rescue, said it was urgent. I landed, and this man here attacked me. I managed to get him under control." * * * * * Gendron looked mystified. "There's been some misunderstanding here. We're in no trouble whatever--in fact, we're doing splendidly. As you can see, we've erected our headquarters building, and we're settling about to map the planet, according to instructions." Carter frowned. "What about this man here?" "You mean Sherman? I'm afraid I can't tell you." The Squadron Leader turned to Carter's captive. "Did you attack this man?" "No," Sherman said. "He jumped me first."