The sight that greeted him was enough to make any man gasp, even one less young and impressionable than Sime. In all of his twenty-five years he had not seen a woman so lovely. Her complexion was the delicate coral pink of the Martian colonials--descendants of the original human settlers who had struggled with, and at last bent to their will, this harsh and inhospitable planet. She was little over five feet tall, although the average Martian is perhaps slightly bigger than his terrestrial cousin. Her hair was dark, like that of most Martians, drawn back from her forehead and fastened at the nape of her neck, from there to fall in an abundant, rippling cascade down her slim, straight back. Her figure was like those delicate and ancient creations of Dresden china to be seen in museums, but elastic, and full of strength. She was dressed in the two-piece garment universally worn by both sexes on Mars--a garment, so historians say, that was called "pyjamas" by our forebears. And she was defiant. In her hand was a stiletto with long, slim blade. Sime made a darting grasp for her wrist and wrung the weapon from her. It fell to the metal floor with a tinkling clatter. "And now tell me, young lady, what's the meaning of this?" Suddenly she smiled. "I came to warn you, Sime Hemingway." She spoke softly and sweetly, and with effortless dignity. "You came to warn me?" "You are in grave danger. Your mission here is known, and powerful enemies are preparing to destroy you." "You talk like you knew something, kid," Sime admitted. "What is my mission here?" "You have been sent to Mars by the I. F. P. in the guise of a mining engineer. You are to discover what you can about a suspected plot of interplanetary financiers to plunge the Earth and Mars into a war." "How so?" Sime asked enigmatically, concealing his dismay at the girl's ready reply. Here was inside information with a vengeance! "Several shiploads of gray industrial diamonds from Venus have been seized by war vessels carrying the insignia of the Martian atmospheric guard." Sime nodded. "Go on!" "Curiously enough, these raids were so timed that they were witnessed by the news telecasters. All of the people on Earth were thus eye-witnesses, and feeling ran high. Am I right?" "Go on!" "And of course you know about the raids on the Martian borium mines by pirates armed with modern weapons. In the fights, some of the pirates' weapons were captured. They bore the ordnance marks of the terrestrial government." "I'm way ahead of you, girlie!" Sime conceded. "Certain financial interests would like to see a war. They're cookin' up these overt acts to get the people all steamed up till they're ready to fight. I'll go further, since you seem to know all about it anyway, and admit that I'm here to find out just who's back of all this. And how does all that tie up with you hiding in my mist-bath with a long and mean lookin' knife?"