Completing Marcel Pagnol's trilogy after Marius and Fanny, Panisse dies, and Cesariot learns from his mother Fanny that his father is Marius.
Cèsar Olivier (Raimu) asks priest Elezar (Thommeray) to come because Honoré Panisse had a heart attack. Panisse (Charpin) says that he is "cooked" and will miss life. Elezar asks Panisse to confess, and Panisse asks the men to stay. Cèsar reads the ten commandments. Panisse admits he lied often and sinned with women. Felix is sent out for being curious. Everyone knows that Cesariot is not his son except Cesariot. Dr. Venelle (Edouard Delmont) tells Elezar not to give extreme unction, because it kills his patients. Panisse refuses to tell Cesariot (André Fouché) that Marius is his father.
Garage mechanic Marius Olivier (Pierre Fresnay) learns from his lazy partner Fernand (Doumel) that Panisse died. Fanny (Orane Demazis) tells Cesariot that Panisse was not his father. She says she and Marius were in love, but he went to sea. Cesariot calls Cèsar grandfather, whom he loved as his godfather. Cesariot asks Cèsar about Marius. Cèsar quarreled with him and threw him out. Fanny asks the stoker to report to her about Cesariot. She says good-bye to Cesariot, who goes in a boat with the stoker. Cesariot goes to Marius to fix his motorboat. Cesariot's school-mate Pierre Dromard (Robert Bassac) visits Fanny, and Cèsar asks if Cesariot is at Pierre's; Fanny says that Pierre lies. The stoker calls Cèsar and says he is with Pierre. Cesariot and Marius go fishing, and Marius talks about his past. Fernand asks Cesariot to smuggle opium. Cesariot picks up the stoker, and they come back. Fanny and Cèsar say they lie. Cesariot tells Fanny that he saw Marius. Fanny tells Cesariot how she loved Marius and then devoted her life to Cesariot. Cesariot sees Fernand and tells him to leave, and Fernand learns that Cesariot is the son of Marius. Cesariot tells Marius that he is Fanny's son. They go to Cèsar and Fanny and discuss the past crimes of Marius and the family. Marius says he kept a woman for five years and sold her to buy his garage. Marius says that Panisse, Fanny, and Cesariot all gained, but he did not. Marius invites Cesariot to come see him and leaves.
Marius drives a car and meets Fanny, telling her he loves her. He says it is too late and that he is only a worker. Fanny asks if she is too old, but he says she is pretty. Fanny says that she hoped he would be free after Panisse died. She says that she is alone and needs Marius. Marius says he will call; but he can't leave because Cèsar prevented his car from starting. Cèsar tells them that Cesariot hopes they will marry. Marius tells Cèsar that Cesariot will not bear their name; but Cèsar says the others will.
With wit and charm this story portrays the friendships and the suspended love between Marius and Fanny and his father Cèsar. Cesariot at age 20 is able to bring back together his parents, who were separated when Marius was that age.