After a family visit, stressed businesswoman Senga Wilson (Madeleine Stowe) is driving with her rebellious daughter, Nat (Mischa Barton), down an ominous highway in the middle of the night. After they pick up a weird teenage hitchhiker (Bijou Phillips), their journey goes awry. Nat decides to give her mom the slip and runs off with the hitchhiker at a rest stop. In a desperate search to find her daughter, Senga learns that Nat has been drawn into an evil cult.
Re-formed by a coded message to their web site, a group of animal rights activists set off to free an imprisoned colleague from a terrifying ordeal. Their rescue mission leads them to a disused lab, but what should have been a simple raid turns into a series of twisted and mind bending incidents where the free and the caged switch places, in this tormented psychological horror.