Leisha Camden was genetically modified at birth to require no sleep, and her normal twin Alice is the control. Problems and envy between the sisters mirror those in the larger world, as society struggles to adjust to a growing pool of people who not only have 30 percent more time to work and study than normal humans, but are also highly intelligent and in perfect health. The Sleepless gradually outgrow their welcome on Earth, and their children escape to an orbiting space station to set up their own society. But Leisha and a few others remain behind, preaching acceptance for all humans, Sleepless and Sleeper alike. With the conspiracy and revenge that unwinds, the world needs a little preaching on tolerance.