Tomas, a German filmmaker living in Paris, wraps production on his latest film. At the cast party at a nightclub, his husband Martin, an English printer, is tired and declines to dance. Tomas dances with Agathe, a young primary school teacher; he later goes to her home and they have sex. The next day, Tomas admits to Martin that he slept with a woman and felt a renewed excitement he has not felt in years. Martin is hurt by Tomas's callousness. When Martin refuses to discuss the state of their marriage immediately, Tomas attempts to pack a suitcase, but Martin stops him, and they share a tender moment. However, Tomas soon meets Agathe at his editing suite, and they resume their affair. Tomas and Martin travel to their country house. Tomas complains that their relationship has become too safe and predictable, while Martin accuses Tomas of falling in love with Agathe. Back in Paris, Martin meets Amad, a writer and novelist, through a mutual friend at a restaurant. When Tomas arrives, he is somewhat hostile towards Amad and later tells Martin he finds Amad "an arrogant prick". As they leave, Tomas claims to be heading to the editing room but goes to Agathe's instead and spends the night there. In the morning, after Agathe sings Tomas a lullaby from her childhood, he confesses he has fallen in love with her. Tomas and Martin separate, and Tomas moves in with Agathe. Returning to the apartment to collect his things, Tomas finds Martin reading Amad's book. Martin informs him he intends to sell the country house. Later, Tomas uses his key to enter the apartment unannounced and finds Amad taking a shower; he storms out in a jealous rage. Following a poor test screening of his film, Tomas seeks comfort from Martin at his workplace, but Martin demands his keys back. Tomas encounters Martin and friends at a restaurant while dining with Agathe, but the men ignore each other. Tomas later forces his way into Martin's apartment, insisting on staying the night so they can repair the country house roof the next morning. Martin relents. That night, Tomas initiates sex with Martin. The next morning, Tomas reveals that Agathe is pregnant. Tomas attends a dinner with Agathe's parents, who interrogate him about his family and his past with Martin. Tomas becomes defensive and hostile. He later returns to Martin, claiming his film's latest screening was a success. He tells Martin he misses being with a man and proposes they raise Agathe's baby together as a family. Martin breaks up with Amad, who warns that the toxic dynamic between Tomas and Martin will destroy them both. Some time later, Agathe, Tomas, and Martin are at the country house. Agathe overhears the two men having sex. That night, Tomas climbs into bed with a weeping Agathe. She subsequently cuts off contact with him. In a lunch meeting with Martin, Agathe reveals she has had an
abortion, realizing she would eventually be erased by the dynamic between the two men. Martin is devastated, because Tomas knew beforehand and hadn't told him. Martin returns to the apartment and ends his relationship with Tomas for good, refusing to go to Venice with him and demanding no further contact. Desperate, Tomas goes to Agathe's school. He begs for forgiveness and asks her to come to Venice with him, but she rejects him and walks away. Tomas gets on his bicycle and rides aimlessly through the streets of Paris. ==Cast==