 After the death of her mother Marianne (Jeanne Balibar), a young cellist discovers that her father had a mistress. In order to find her, she casts aside her boyfriend Etienne (Renaud Becard). The mistress is a pianist named Beatrice (Bulle Ogier). Beatrice and Marianne strike up a friendship while reminiscing about the past. They remember Edith Piaf s song : "Hymne à l amour" and Marianne reconnects with her nanny Ghislaine (Valerie Crunchant) who was a funny companion when she was young.