And he had the wallet. When he paid for the first round of _culcha_, he took it out and stole a glance at the identification card inside. There it was--his ticket to freedom. He began feeling expansive, and even friendly toward the slender, mouse-like man across the table. It was the _culcha_, of course. He knew it, and didn't care. In the morning he'd find a freighter berth--in as big a spaceport as Lillis, there were always jobs open. Meanwhile, he might as well enjoy himself, and it was safer to be seen with a companion than to be alone. He listened lazily to what the other was saying, leaning his tall, graceful body back into the softly-cushioned seat. "Lissen," said Harold Tate. He leaned forward on one elbow, slipped, caught himself, and looked at the elbow reproachfully. "Lissen," he said again, "I trust you, Jones. You're obvi-obviously an adventurer, but you have an honest face. I can't see it very well at the moment, but I hic!--pardon--seem to recall it as an honest face. I'm going to tell you something, because I need your help!--help." He paused. "I need a guide. D'you know this part of Mars well?" "Sure," said Syme absently. Out in the center of the floor, an AG plate had been turned on. Five Venusian girls were diving and twisting in its influence, propelling themselves by the motion of their delicately-webbed feet and trailing long gauzy streamers of synthesilk after them. Syme watched them through narrowed lids, feeling the glow of _culcha_ inside him. "I wanta go to Kal-Jmar," said Tate. Syme snapped to attention, every nerve tingling. An indefinable sense, a hunch that had served him well before, told him that something big was coming--something that promised adventure and loot for Syme Rector. "Why?" he asked softly. "Why to Kal-Jmar?" Harold Tate told him, and later, when Syme had taken him to his rooms, he showed him what was in his little black suitcase. Syme had been right; it was big. * * * * * Kal-Jmar was the riddle of the Solar System. It was the only remaining city of the ancient Martian race--the race that, legends said, had risen to greater heights than any other Solar culture. The machines, the artifacts, the records of the Martians were all there, perfectly preserved inside the city's bubble-like dome, after God knew how many thousands of years. But they couldn't be reached. For Kal-Jmar's dome was not the thing of steelite that protected Lillis: it was a tenuous, globular field of force that defied analysis as it defied explosives and diamond drills. The field extended both above and below the ground, and tunneling was of no avail. No one knew what had happened to the Martians, whether they were the ancestors of the present decadent Martian race, or a different species. No one knew anything about them or about Kal-Jmar.