Renowned lawyer, Sophie Humbert works with her husband, Olivier Merle, in a Bordeaux law firm. They both go from strength to strength. Sophie defends in particular the interests of the police headquarters. Inès, Olivier's daughter, is an ex officio lawyer. She is called to defend a young man, Gabriel Etchegeray, accused of having killed a police officer. The young man has just confessed. Wanting to help her, Sophie is challenged by the date of birth of the accused and decides to take over the case, to the dismay of her daughter-in-law and her husband.