In this unforgettable conclusion to Nancy Kress' groundbreaking trilogy which began with the Nebula Award–winning Beggars in Spain, it is now two hundred years in the future. Regular human beings hate and fear the Sleepless and the SuperSleepless, genetically modified humans who are immune to disease and hunger and do not need to sleep. When the Sleepless plot to take over the world and leave regular humans powerless, civilization and the very meaning of the word "human" hang in the balance.