Sarah Morton (Charlotte Rampling), a middle-aged English mystery author, who has written a successful series of novels featuring a single detective, is having writer's block that is impeding her next book. Sarah's publisher, John Bosload (Charles Dance), offers her his country house near Lacoste, France for some rest and relaxation. After becoming comfortable with the run of the house, Sarah's quietude is disrupted by a young woman claiming to be the publisher's daughter, Julie (Ludivine Sagnier). She shows up one night claiming to be taking time off from work herself. She also claims that her mother used to be Bosload's mistress, but that he would not leave his family. Julie's sex life consists of one-night stands with various oafish men, and a competition of personalities develops between the two women. At first Sarah regards Julie as a distraction from her writing. She uses earplugs to allow her to sleep during Julie's noisy nighttime adventures, although she nonetheless has a voyeuristic fascination with them. Later she abandons the earplugs during one of Julie's trysts, beginning to envy Julie's lifestyle. The competition comes to the fore when a local waiter, Franck (Jean-Marie Lamour), is involved. Julie wants him but he appears to prefer the more mature Sarah, having struck up a relationship with her during her frequent lunches at the bistro.An unexpected tragedy occurs after a night of flirting among the three. After swimming together in the pool, Franck refuses to allow Julie to continue performing oral sex on him, once Sarah, who watches them from the balcony, throws a rock into the water. Franck feels frightened and tells Julie he is leaving. The next day, Franck is missing. While investigating Franck's disappearance, Sarah learns that Julie's mother has been dead for some time, though Julie had claimed that she was still alive. She returns to the villa, where a confused Julie thinks that Sarah is her mother and has a breakdown. She eventually recovers and confesses that Franck is dead because Julie repeatedly hit him over the head with a rock as he tried to leave her at the pool. His body is in one of the sheds.When Marcel (Marc Fayolle) becomes suspicious of the mound of fresh soil where the body is buried, Sarah seduces the elderly gardener to distract him. Julie leaves, thanking Sarah for her help and leaving her the manuscript of an unpublished novel