Helen and Rachel McCallister, who live in a town called Roam, are as different as sisters can be: Helen, older, bitter, and conniving; Rachel, beautiful, naive--and blind. When their parents die suddenly, Rachel has to rely on Helen for everything, but Helen embraces her role in all the wrong ways, convincing Rachel that the world is a dark and dangerous place she couldn't possibly survive on her own . . . or so Helen believes, until Rachel makes a surprising choice that turns both their worlds upside down.