Le code a changé

The film is centered around a dinner that takes place every year between a group of Parisian friends during the "Fête de la Musique". Piotr, the husband of Marie-Laurence, who is an overworked lawyer, is on sabbatical leave so it is up to him to organise the dinner party. The dinner does not go as planned: Lucas quarrels with his wife Sarah, Melanie decides that this is the perfect time to confess her extra-marital affair to her husband Alain. Juliette, Marie-Laurence's sister, comes with a surprise guest, Erwann her new companion, who is thirty years older than her. The arrival of Henri, the father of Juliette and Marie-Laurence, is a further upheaval because Juliette is not on speaking terms with him.