On the last day of World War I, German fighter pilots Erich Lohkamp, Robert Taylor and Gottfried Lenz, Robert Young, along with Otto Koster, Franchot Tone, share a fatalistic outlook about what lies ahead. After the armistice, they drift into an auto-repair business, barely scraping by as they chase a sense of purpose in peacetime.
Several years pass, and while driving to a country inn they meet Herr Breuer, [Lionel Atwill], a prosperous fascist sympathizer, and Pat Hollmann, [Margaret Sullavan], an aristocrat who has fallen on hard times. Although she is worldly, Pat is drawn to Erich's quiet honesty, and they soon arrange a date.
At the opera, Breuer reappears and invites them to a nightclub, from which Erich leaves in embarrassment over the social gap between them. Pat's conviction grows that their love can overcome class barriers, and they acknowledge their true feelings for each other.
Behind the scenes, Gottfried urges Erich to marry Pat, while Otto urges Pat to marry Erich. Pat reveals to Otto that she is suffering from tuberculosis. Otto convinces her that she should still marry Erich, setting the stage for a precarious happiness.
On their honeymoon, Pat collapses while playing on the beach and Erich remains oblivious to her illness. When the truth comes out, Dr. Jaffe [Monty Woolley] intervenes, warning that Pat must be admitted to a sanitarium by October. The summer passes with a fragile joy, shadowed by the looming illness.
Meanwhile Gottfried's loyalty is tested between his friends and his pacifist beliefs in Dr. Becker, [Henry Hull], whose teachings weigh on them all. A tragedy strikes when a thug kills Gottfried while trying to attack Dr. Becker, throwing the circle into turmoil. Erich and Otto vow to track down the killer, selling their shop and following leads through the winter and into Christmas, ending with a deadly church confrontation in which Otto kills the murderer.
Pat's operation to collapse her lung costs more than 1,000 marks, and Erich insists on paying, even as Otto sacrifices his car to help. After recovery, Pat pleads with Otto to stop sacrificing for her sake, arguing that her future care will be endless and expensive. She longs to seize happiness now and suggests escaping to Rio with Erich and Otto, but Erich urges patience and focus on recovery.
Pat eventually makes a choice that tests them all: she steps toward risk, her movements on the balcony hinting at her end. Erich races to her side just as she collapses, her final words of love echoing. Following her funeral, as street fighting rages between fascists and protesters, Otto and Erich decide to flee to South America. As they walk away from the cemetery, the spirits of Gottfried and Pat walk beside them, offering a quiet blessing on their new life.
