During Mardi Gras celebrations, Jourdain escapes and takes up residence in the Pension Beau Soleil, a run-down boarding house in Nice inhabited by several unhappy individuals, including the owner's shy daughter Lydia, the suicidal Russian exile Fédor, and the embittered spinster Miss Aglaé.

Jourdain hires some actors from the local theatre to play roles in real life at the boarding house which will transform the lives of everyone, illustrating his principle: "To create the happiness of others is difficult.

The leading actor and tenor Félix courts Lydia and makes her feel loved, his wife Anita awakens the interest of Fédor, and Déribin overcomes his aversion to Aglaé and listens to her complaints.

To bring his scheme to its completion, Jourdain organises a fancy-dress ball which culminates in an invasion of the local studios of Radio Azur by all the masked revellers, and a succession of mistaken identities, tricks and unmaskings results in the confused satisfaction of almost everyone.

Marcel L'Herbier had wanted for many years to make a film from Nikolai Evreinov's 1921 play Samoe glavnoe which, as La Comédie du bonheur, had enjoyed success on stage in the 1920s in France and elsewhere.

[2] It was another ten years before circumstances allowed the project to proceed with a new producer, André Paulvé, and it did so under the imminent threat of World War II breaking out in Europe.

[3][4] A prestigious cast was assembled led by Michel Simon, and it included early appearances by Micheline Presle and Louis Jourdan (his first completed film).