Kristina Georgia Snow is the perfect daughter： gifted high school junior, quiet, never any trouble. But on a trip to visit her absentee father, Kristina disappears and Bree takes her place. Bree is the exact opposite of Kristina －－ she's fearless. Through a boy, Bree meets the monster： crank. And what begins as a wild, ecstatic ride turns into a struggle through hell for her mind, her soul －－ her life.