The prologue introduces Paul Godard, a filmmaker, and his estranged girlfriend, Denise, in which a stressed Paul leaves the deluxe hotel to which he has moved and rebuffs the sexual advances of a male hotel attendant.
The first section, “The Imaginary,” follows Denise as she takes her first steps to an independent life without Paul. She lands a manual job on a local paper run by an old friend, perhaps an old lover, in a country town and gets a room on a farm in return for helping with the cattle. She is also writing up some new project, which may become a novel. At the same time, she has to complete her job at the television station where she and Paul work, as well as find a new tenant for her flat in the city where she and Paul have been living together. Realising she is late to collect the author and filmmaker Marguerite Duras for an interview, she telephones Paul to ask if he can do it for her. Despite being in no mood to agree with her, he accepts.
The second section, “Fear,” focuses on Paul. He is afraid of life without Denise, perhaps of life itself. After picking up his surly daughter Cécile from soccer practice, at which seemingly apropos of nothing he asks the coach if he has ever felt like touching or having sex with his own daughter, he fulfils his favour to Denise by collecting Marguerite Duras from a local college, where she was due to give a talk. When she refuses to do so (her voice is heard but she is not shown), Paul reads out some of her notes, in which she says that she only makes films because she lacks the courage to do nothing. Paul says this is true for himself as well. The celebrity then gets Paul to take her back to the airport, after which he has to face a furious Denise who has lost her interviewee. That evening, as it is Cécile’s birthday, he takes her and her mother to a restaurant but all his scornful ex-wife wants is money and all the girl wants is presents. Leaving in fury, after again expressing his alienation with inappropriate sexual innuendo, he meets Denise in a bar, where the two quarrel and part. Standing alone in a late-night cinema queue, he is picked up by the prostitute Isabelle.
Part Three, “Commerce,” is Isabelle’s section, in which she devotes herself to increasing her earnings in order to achieve independence. After her night with Paul, in which she mechanically goes through the motions while mentally planning her next day, she is waylaid by a pimp who gives her a spanking to remind her that there is no independence in a commercial world and he must have 50% of her earnings. On returning to the apartment she shares with some other women, who all seem to detest her, her younger sister arrives unexpectedly and asks Isabelle for money because her lover and all his associates have just been jailed for robbing a bank. When Isabelle refuses, the sister asks if she will get her started in the local prostitution business. Isabelle agrees to coach her for a month, in exchange for 50% of the take. While continuing to service a variety of clients with different needs, sometimes inventive (one businessman choreographs a foursome while sitting at his desk), and all the while with her mind elsewhere, she is also searching for an apartment of her own. An old school friend she meets in a hotel corridor, probably a dealer and maybe a prostitute as well, offers her a lucrative opportunity to be a courier, but the boss of the operation finds Isabelle too dangerously naive. Going to inspect an apartment, it turns out to be that of Denise, and Paul is also there trying to rekindle the relationship. Isabelle and Denise form an immediate bond.
In the coda, entitled “Music,” Isabelle seems to prosper in her new apartment and Denise has moved on in life. After having spent several days adrift, Paul runs into his ex-wife and daughter and asks plaintively to spend more time with them. Walking backwards away from the two, Paul accidentally steps in front of a car and is hit. Isabelle’s sister, now apparently a prostitute, flees the scene with the driver of the car, her client. Paul’s ex-wife also urges Cécile to come away, saying “it’s nothing to do with us.” As the two walk off, they pass a small orchestra set up in a garage yard that is playing the theme music which has echoed through the film.