Sequel to Ender's Game (1984) and Speaker for the Dead (1986), exploring the problems of alien contact and coexistence on planet Lusitania, where now three intelligent species dwell: human colonists; "buggers" (an arachnoid Hive Queen reasserts herself after the near extinction of her species in the human-bugger war); and the indigenous "piggies," who, after a horrid flaying-alive ceremony, metamorphose into sapient trees. But the planet is rife with descolada virus; this mediates the transformation of piggies into trees, but in humans mutates into a deadly, ineradicable plague. Rather than permit the descolada to spread, Earth sends a battle fleet to blast Lusitania. Once again, Ender Wiggin and his sister Valentine will play prominent roles in the search for a solution--the upshot being, thanks to time travel, a "rescolada" rescue-virus that promises to turn a potential plague into a fabulous biological tool. Splendid plotting--if you can stomach Card's repulsive transcendence-through-torture notions; and, what with the frequent, irksome, and interminable theological/philosophical interludes, it's hard to escape the conclusion that Card's true purpose here is to preach rather than simply tell a story.