Sophomore Hallie Calhoun has just endured the most excruciating six months of her life. Once the rumors about her and the preacher's son, Luke, made their way around school, her friends abandoned her, and Hallie has completely withdrawn. Now, on a hike in the Smoky Mountains with the same people who have relentlessly taunted her, Hallie is pushed to her limit. Then Hallie, outgoing newcomer Rachel, and Hallie's former friend, Jonah, get separated from the rest of the group. As days go by without rescue, their struggle for survival turns deadly.