On n'aime qu'une fois

Envoi de Fleurs is based on incidents in the life of French composer Paul Delmet. Played by popular French singing star Tino Rossi, Delmet is depicted as a man all too willing to give up personal happiness in favor of blind ambition. After carrying on a romance by correspondence with beautiful young Suzanne (Micheline Francey), Delmet is on the verge of marrying the girl. Instead, he allows himself to be talked out of leaving France to further his own career, with disastrous results for all concerned.

Hélène has an affair with Alain for ten years, but does not want to divorce her husband. Alain receives one letter from a girl Michelle one day. Hélène, who is very jealous, receives that letter by chance and interprets it incorrectly.

Bernard Lampré, a young composer, is engaged to Hélène Madelin, a gifted intern. Jealous of Professor d'Esperel, the great surgeon she proudly assists, Bernard, goes out and wanders in the rain all night long. He catches cold, falls ill and is sent to a sanitarium. There he meets again Jacqueline, a girl who studied music with him at the Conservatoire. Learning that she is dying, Bernard decides to play the comedy of love to soften her last moments.

The Secret Service abducts a "rocket scientist" to better protect him against gangsters acting for Chinese agents.

Daniel Gelin and Juliette Faber star as a blissfully happy honeymooning couple. They are so happy that they arouse the jealous attentions of Satan. The Dark Prince sends an emissary to beak up the romance, but his advocate is promptly challenged by a representative from "up above."

In 1914, in the first months of World War I, Louise Jarraud loses her husband, killed on the front. Shortly after, she gives birth to a baby, who soon dies. Devastated by this double misfortune, Louise decides to dedicate her life to caring for the children of others. She becomes a nurse with several employers, giving her affection to little boys or girls. A widower and another man propose to her but she refuses twice determined as she is to live only for the children in her charge.

Marie Leroux, who is married to Charles, an honest, understanding country doctor, lives an uneventful, rather monotonous life.Her husband is a kind man but he does not give her any thrill or excitement. One day, Marie meets Olivier Dumas-Beaulieu, a handsome industrialist, who is in the process of leaving his fiancée Corinne, despite her being pregnant by him. It is easy for the confirmed womanizer he is, to seduce Marie, who very foolishly thinks she has found true love. Shortly afterward Charles is shot dead by Olivier while the two men were having a quarrel about Marie. The latter, who finds the corpse, believes her husband has committed suicide. Which is not the police's opinion and Marie is arrested and condemned to ten years in prison. Annihilated by such unfair treatment and, worse, by the separation from her beloved eight-year-old daughter, she still manages to survive and to serve her sentence.