"Right." Dry-lipped, Boone pivoted and strode towards the door, gesturing to the ensign. "Come on." The other nodded and fell in beside him. "Where do you want to start?" "Top live cargo section." Together they rode the lift to the highest level, then walked to the end of the "A" passage. Boone kicked the hatch of the first bunker. "Open it up." "Open it--?" The ensign's eyes widened. "You mean you're going to check inside, too?" Boone nodded curtly. "That's right." "Well, if you say so...." Frowning, the ensign broke the seal; swung back the hatch. Cold air washed over them. Light glinted on the seven-foot synthice slabs stacked floor to ceiling, each casing a contract worker stiff in frozen sleep. Narrow-eyed, Boone probed each nook and crevice with his light-rod, then stepped back. "All right. Let's have the next one." The ensign slammed shut the hatch. He studied Boone curiously. "Just what are you looking for?" Boone shrugged. "Monsters don't come out of nowhere; not really. My bet is that they get aboard our ships at the Titan base--in embryo, maybe, or as a virus. If we can spot one before it's grown to a full-scale nightmare, it may give us a hint as to how to beat them." "But they say they're human, sometimes--" "Maybe. But no man I know can appear and disappear at will, and so far we're the only humanoid race we've found anywhere in the system. Till I see more proof, I'll put my money on alien life-forms plus optical illusion." "Oh." The ensign's brows drew together. He opened the next hatch. Another blank. It went on like that, section after section. They checked supply storage, power receptors, converters. Still nothing. In the control room, when they got there, Japetus was already fading from the visiscreen. Hyperion loomed ahead, a bead-like dot hovering in the shadow of the Rings. Beyond it, dim and distant, lay Titan. Titan, greatest satellite of Saturn, nearly half the size of Earth itself. Titan, that had given Man mekronal, the precious, mysterious catalyst that cut loose the human race from the need for the oxygen-nitrogen atmosphere of its homeland. Titan, world of lost sphere-ships and phantasmic monsters. Bleakly, Boone wondered if he'd ever reach it. Or even if he did, would Eileen Rey live to see it with him? What were the odds against a woman struck down by Titan fever? Those were questions without answers. Weary, tight-lipped, he turned from the screen. "Nothing here. Let's try the crew quarters." "Good enough." Once again, the ensign fell in beside him. Overhead, the alarm bell clanged. * * * * * Boone went rigid; spun about as the com-box crackled, raw and ragged: "Top level calling! There's something in "A" passage--something awful! Get the biologist--Oh, my God--!" A scream: the scream of a soul in torment. The com-box went dead. The ensign at his heels, Boone raced for the lift-shaft. The top level, "A" passage. The lights at the far end were out.