The scientist-colonists of the Aurora Corporation's expedition to Eridan are half-crazed with greed for the jewel-like crystals scattered over the planet--and an inexplicable fear has already brought mutiny and the murder of the expedition's most famous scientists, the Orlovs. Biologist Theodora Leslie rescues their daughter Karen near her research camp in the mountains. Though Theo's home base may have mutinied as well, the two are forced to return there by the wet season's drenching rains, and in a dry cave en route they discover a new creature-species, a sort of freeze-dried caterpillar. Then, back at Base Three, they learn that their ""cave bears"" have reconstituted in the rain and put in a grisly appearance: ""I know what this is on the floor in there. Staff."" The tragedy intensifies the scientists' panic, which Theo traces to the crystals--they're really a virus--before the Corporation's Vice Regent arrives to get the expedition off Eridan. Once past the pretentious prologue (""It has beauty, that world, so much beauty""), this is straight adventure, brisker and more human than The Delikon (p. 435, J-115).