A husky, rumbling voice broke the silence. "I wouldn't struggle, Earthman, if I were you. Even should you get free I still have my ray-tube. And my little friends would ask nothing better than your body to play with." Darl writhed to a sitting posture. Now he could see his mysterious abductor clearly. This eight-foot, blue-feathered individual, with curved beak and beady eyes glittering from his naked, repulsively wrinkled head, was a Martian! Despite the human shape of his body, despite his jointed limbs and thumbed hands, this denizen of the red planet resembled a vulture far more than he did any other Earth creature. * * * * * The Earthman's pride of race came to his rescue. "What's the game?" he growled. "Looking for trouble?" There was nothing in Darl's voice to show the fear that chilled him. Behind the Martian he could see vaguely a group of little yellow Mercurians. "I'll ask all the questions here. And you'll answer them, too, if you're wise. Even your dull mind should comprehend that you are in my power." Darl decided to proceed more cautiously. "What do you want from me?" he asked. "I want," the Martian answered, "the recognition signal of Earth's space-ships." "What!" The ejaculation burst from Darl's throat. This alien wanted the secret code, the watch-word that distinguished Earth's space ships, that gained for them free admittance to ITA's armed posts on the outer planets! This could mean only one thing, that the long rivalry, the ancient dispute between Earth and Mars was about to flare into open war. Any friendly visit from a foreign flier would be heralded by word from M-I-T-A. Thomas' face became a stony mask, covering the tumult of his mind. "You understood. I want the Earth recognition signal at once--and after that, the surrender of the Dome." The very calmness of the husky tones was a threat. "Never!" "I warn you, Darl Thomas. It would be the better part of wisdom for you to yield willingly what I ask. You will give in eventually, and the means of persuasion I shall use will not be exactly--pleasant." "You'll get nothing from me!" The outlander's lidless eyes were filmed with a gray membrane. His head thrust forward, the feathered ruff beneath it bristled. Darl braced himself to withstand the swooping pounce that seemed imminent, the slash of the sharp beak. A burring rattle broke the momentary hush. The Martian relaxed, turned to the Mercurian from whom the sound had come and replied with staccato vibrance. * * * * *