Plot
Jack, a young British hitchhiker in the French countryside, attempts to get a ride to the ferry service back to England. After walking along the road for hours without having any cars stop, he comes upon an arguing couple who pull over and continue their fight. Concerned, Jack approaches the car and pulls the man out before he can strike the woman. The man backs off from Jack and drives away, leaving Jack with the woman, who introduces herself as a fellow hitchhiker named Véronique. Véronique tells him that there is a serial killer active on this road, which explains why Jack could not get a ride. The two agree to travel together for safety, and Véronique helps him work on his French. Véronique says she is a drifter whose parents blame her for her brother's accidental death, and Jack that, on the same day, he lost all his luggage and found his girlfriend cheating on him.
An eccentric man, Grizard, stops and offers the two a ride. Although Véronique is reluctant, Jack convinces her to accept Grizard's offer. When Grizard discovers that Jack is English, he enthusiastically invites Jack to meet his English wife. Véronique protests at the detour, but Jack again convinces her to accept Grizard's hospitality. On the way to his house, Grizard stops to pick up roadkill and laughs when Jack suggests they bury it instead of eating it. Mary, Grizard's wife, turns out to be American, though she says she has also lived in England. During dinner, Jack reveals that he is a vegetarian and apologetically declines to eat their meat. Grizard mocks him in French, upsetting Mary and Véronique. When the conversation turns to the serial killer, Mary becomes upset and leaves the table. Grizard insists they are safe in his house and urges them to stay the night.
Grizard puts Jack and Véronique in separate bedrooms. Jack finds photographs of a boy and girl in his room, but Grizard tells Jack they have no children. Before Jack goes to bed, Mary advises him to lock his door, which he does. That night, Véronique enters his bedroom, and they have sex. Jack invites her to come to England with him, and she excitedly accepts. When he wakes, she is nowhere to be found. Grizard says she has left and produces a note. Although Jack is suspicious, Grizard insists he immediately leave the house. As he leaves, Jack realises the handwriting on the note is not Véronique's. Before he can do anything else, he is drugged and kidnapped by Grizard's handyman, Delacroix. Delacroix says Jack must have annoyed Grizard a great deal, and, in French, variously threatens and mocks Jack; Jack says he does not understand and begs to be let go. Delacroix ties up Jack and puts him in his truck, but, before Delaxcroix can drive off, Jack escapes. Delacroix says to himself that Jack is in even worse trouble now that he has escaped.
Jack returns to Grizard's house, where he finds Véronique tied up. After freeing her, he arms himself with a shotgun. Jack and Véronique escape the house in a stolen car, pursued by Grizard and Mary, who have returned home. After a car chase in which their car flips, Jack and Véronique flee on foot.
They encounter Delacroix, who, after a scuffle, accidentally impales himself on a farm tool. While Jack is not looking, Véronique kills Delacroix with a knife. Grizard and Mary find her and he has a vision of Véronique was a child, revealing her as their daughter. She claims then, as she does now, that she did not murder anyone and the death was accidental. In French, Mary and Grizard, revealed to be Véronique's parents, plead with her to return home and stop killing people, saying they cannot cover for her any more.
Véronique refuses. Before Mary can tell Jack the truth in English, Véronique knocks Mary unconscious with the shotgun and gags Grizard. As Véronique and Jack drive off together, Véronique checks to make sure she has Delacroix's knife. After the credits, Mary wakes up and cries at losing her daughter and Grizard despairs while gagged.
