"In the near-future United States, a one-child policy is ruthlessly enforced ... But Ava Goodwin, daughter of the head of the Texas Family Planning Division, has a secret--one her mother died to keep and her father has helped to hide for her entire life. She has an identical twin sister, Mira. For eighteen years Ava and Mira have lived as one, trading places day after day, maintaining an interchangeable existence down to the most telling detail. But...