This second part of Marcel Pagnol's trilogy about Marseille picks up where Marius left off.
Fanny has fainted after Marius left on a ship for five years. Cesar (Raimu) tells his friend Honoré Panisse (Charpin) he is happy Marius is marrying Fanny. Cesar and Fanny's mother Norine (Alida Rouffe) petulantly agree on this. Then Fanny (Orane Demazis) tells them Marius is gone and that she told him to go. Cesar is irritable, and no letter has come for 29 days. He tells his friends not to talk about Marius.
When a letter arrives for Cesar, he has Fanny read it aloud. Marius hopes that Fanny will be happy marrying Panisse. Cesar dictates a letter that Fanny writes down, but she suggests changing the part about her sadness. Panisse asks Norine for Fanny's hand, and they discuss how he would act if she betrayed him. Fanny goes to church and prays for Marius to return to name her child. She tells her mother she is pregnant and faints when Norine gets angry at her. Norine says to marry Panisse and not mention the baby. Fanny disagrees, preferring to be honest; she visits Panisse and tells him about the baby. When he is understanding, she agrees to marry him. Panisse is delighted he will be able to add "and son" to his business sign. When he tells Cesar of the wedding, Cesar forbids it and accuses Panisse of buying her. They threaten each other and recall their past struggles. Cesar asks Fanny if it is true, and she replies that she needs a husband. Then Cesar accuses her of marrying for money. Panisse tells Cesar of the baby. Cesar is happy to have a grandchild but cannot guarantee that Marius will return to marry Fanny. He suggests the name Cesar Marius Panisse.
Panisse weds Fanny, and seven months later she gives birth to a boy. Cesar tells Norine he did not inform Marius of the child. One night Marius (Pierre Fresnay) returns to Cesar for a brief visit. They talk while Marius eats. Panisse is leaving for Paris in order to sell motorcars. Marius visits Fanny, who says her husband is sleeping. Marius says he is leaving in two hours, and both claim to be happy. Marius realizes the child is his, and he asks Fanny for forgiveness. He has missed her and starts to kiss her when Cesar comes in and will not leave them alone. Panisse returns unexpectedly. Marius wants Fanny back, and they argue over the child. Fanny says Marius is no longer the father, and Cesar agrees the father is the one who loves the child. Fanny will not give her child to Marius even though she still loves him; she tells him to go to sea. Cesar loves Marius but respects the rights of Panisse. Marius says he will never love anyone but Fanny and leaves.
Social morality and the home he can provide cause Fanny to accept Panisse as a husband and father of her child by Marius. Even Cesar tells Marius that Panisse has become the real father by caring for the child.