Rémi, Patrick Dewaere, is a struggling pianist trying to keep his life together after his wife Martine, Nicole Garcia, a model who is aging out of desirable work, is killed in a car crash. Their 14-year-old stepdaughter Marion expresses a wish to stay with Rémi in their apartment, but she is taken away by her father Charly, Maurice Ronet, an alcoholic who dislikes Rémi. Marion eventually returns, and to help make ends meet she begins babysitting while Rémi teaches piano. The fragile balance in their lives shifts as Marion reveals a troubling attraction to Rémi, and he, wary of the huge age gap, tries to resist.
As Marion proves she is physically fragile—anemic, in fact—her father takes her to the mountains, leaving Rémi without their home. He loses his apartment and ends up moving in with friends Simone and Nicolas, Geneviève Mnich and Maurice Risch. In this broken state, he reconnects with Marion, and the two slip into a secret encounter in a hotel. Marion returns to the shared space Rémi has carved out in a run-down, condemned house, where at first he resists further intimacy, then gradually gives in to the pull he cannot fully deny.
During a surprise visit, Charly notices the bond between them and confronts Rémi, asking outright if they are having an affair. Rémi defends himself, and Charly, in a rare moment of vulnerability, apologizes and leaves, unable to fully reconcile his own harsh judgments with the complexity of the situation. The fragile patience of the trio is tested as Marion, while babysitting a little girl named Nathalie, falls ill with the flu. Marion rushes to Rémi for help and, with money borrowed for medicine, he encounters Charlotte, Nathalie’s mother, a skilled pianist herself who captures his interest.
Charlotte, Nathalie Baye, becomes a new focal point for Rémi’s longing, and he begins pursuing her, leaving Marion feeling abandoned and misunderstood in her roles as lover and caregiver. Marion packs her belongings, telling Charly she intends to move back in with him, even as the emotional world she hoped to share with Rémi crumbles around her.
Despite the heartbreak, Rémi cannot fully escape the ache that led him here and seeks out Charlotte. In a moment of shared vulnerability, they have sex, unaware that Nathalie, the little girl, witnesses the encounter, adding another layer of conflict and secrecy to their already precarious lives. The film thus threads together desire, guilt, loyalty, and the consequences of a love that has thrived in shadows, leaving all involved to face the consequences of their choices in a world where connections are fragile and the line between need and danger is never clear.
