Marianne Jannetier, a well-to-do Parisian, engaged to Andre Benoit, a high-ranking government official, flees the city when the goose-stepping Nazi storm-troopers arrive. When her mother dies on the road to Bordeaux as a result of Nazi bombing, she returns to Paris and joins the underground movement. Nicholas Jordan, an American member of the RAF, stranded in Paris after the evacuation is also working with the Paris underground. Marianne kills her former fiancée, a pro-Nazi informant, for the traitorous state papers he is carrying, and she and Jordan try to flee over a French seaport...

A vaudeville comic and a pretty young dancer aren't having much luck in their separate careers, so they decide to combine their acts. In order to save money on the road, they get married. Soon their act begins to catch on, and they find themselves booked onto Broadway. They also realize that they actually are in love with each other, but just when things are starting to look up, the comic starts to let success go to his head.

A tale of the World War I love affair, begun in Italy, between American ambulance driver Lt. Frederic Henry and British nurse Catherine Barkley. Eventually separated by Frederic's transfer, tremendous challenges and difficult decisions face each as the war rages on.