This is 1958 and the Lorskie family are spending their holidays in La Baule-les-Pins, Loire-Atlantique, only this year it's different because divorce is looming, and Kurys investigates the question both from the point of view of the parents and the children. Léna (Nathalie Baye) and Michel (Richard Berry) and their daughters, Frédérique (Julie Bataille) and Sophie (Candice Lefranc), stay with Léna's sister Bella (Zabou Breitman) and her husband Léon (Jean-Pierre Bacri), who have four children. This time, however, Léna joins the group some days later, as does Michel separately.
The main difference though is that Léna's lover Jean-Claude (Vincent Lindon) has surreptitiously come to La Baule and is 'secretly' but increasingly obviously meeting Léna. The, er, climax is when Michel loses his temper with Léna and would have no doubt seriously injured her if Fréderique hadn't intervened.