It's 1969. The conflict in Vietnam has exploded to immeasurable proportions, and 18-year-old Dean Hill's (Taylor Handley
) number is up. But first, Dean, his brother Eric (Matthew Bomer) and their respective girlfriends, Bailey (Diora Baird
) and Chrissie (Jordana Brewster
) head across Texas for a final fling of serious fun.
Soon after their journey begins, the spirited foursome are spooked by a menacing pair of bikers, Holden and his girlfriend, Alex. When Alex chases the group's jeep, propelling them into a serious accident, Chrissie is thrown from the vehicle. As Alex attempts to rob the injured trio, Sheriff Hoyt (R. Lee Ermey) arrives on the scene. Hidden in the nearby brush, Chrissie watches as the sheriff kills Alex in cold blood and then taunts her friends before ordering them into the back of the patrol car.
Hoyt heads to the Hewitt family home where Thomas, who is being groomed to become the terrifying monster known as Leatherface (Andrew Bryniarski), and the rest of the Hewitt clan await. In an effort to save her friends, Chrissie attempts to convince Holden to help her, but he is on a one-man rampage to avenge his girlfriend's death. As Chrissie witnesses the horrors inflicted by the Hewitt family upon the people she loves, she realizes she is their only hope of survival.