For years, best friends Sarah and Jennifer kept a "Never List": things to be avoided, for safety's sake, at all costs. Yet one night, against their best instincts, they accept a cab ride with everlasting consequences. For the next three years, they are held with two other girls in a cellar by a connoisseur of sadism. Jennifer never makes it out. Ten years later, the abductor is up for parole and Sarah can no longer ignore the twisted letters he sent from jail.