Beneath the spaceboat the desert rolled. Vast Saturn and his multiple moons, hung against the black and all-but-airless star-curtain. Then, all of a sudden, before the eastward hurtling craft, it was daylight, as the tiny sun burst over the horizon. Its wan rays fell on pale, stratified mists of air, all but frozen in the cold of night. Those mists, cupped between the hills, were the last of Titan's atmosphere. Once, eons ago, when monster Saturn had been hot enough to supplement the far-off sun's heat with radiation of its own, those hills had been, for a few brief ages, verdant with primitive, mossy growths. Bert followed the dry bed of an ancient river, till he came to the rocky cleft where the _Prometheus_ had been concealed. Just as they glimpsed the ship, Alice gave a sharp gasp, as they saw another spaceboat dart unhurriedly away. Bert landed in the rocky gorge, and on foot they approached the _Prometheus_ cautiously, the blasters from the cabin of the spaceboat gripped in their gauntleted hands. They found the ship's airlock securely bolted. But someone had tried to cut through its tough, heat-resistant shell with a blaster for the metal was still hot. "A break," Bert breathed raggedly. "We got here just in time to scare them off.... Hey!..." That was when they found Doc Kramer. He lay behind a boulder, a pathetic little figure who seemed to be merely sleeping. There wasn't a mark on him that could be easily discovered. There was no time to figure out how he had died--by poisoned needle, overstrong paralyzer beam, or whatever. His body, within its spacesuit, was just beginning to develop rigor mortis. Alice's eyes were wet, her small jaw set hard. "Your brother's death was at least an unintentional accident caused by carelessly made equipment, Bert," she said. "But Doc was murdered." "Yeah," Bert grated thickly. "Only murder is awful hard to prove as far from civilization as this. Come on, we can't do a thing about it right now." * * * * * Double rage and grief drove him on toward what he must do with greater insistence than before. With a key from his hip-pouch, he opened the airlock of the _Prometheus_. With great caution they went inside but found no one in the ship. The mood of its interior was brooding and sullen. Every cubic foot of space not taken up by its machinery and fuel was packed with black ingots of an alloy, a large proportion of which was fissionable metal, quiescent now, and harmless, but under the right kind of primer, capable of bursting into a specialized hell of energy. Five thousand tons of the stuff, Earth-weight!