A college professor marries a night-club singer and has trouble telling his parents and fiancé about it.
Peter Morgan (James Stewart) finds his cousin Keith Morgan (James Ellison) drunk at a night-club and calls his father. Francey Brent (Ginger Rogers) sings "You'll Be Reminded of Me," and Peter is enchanted with her. Peter takes Francey out till morning. Peter finds Keith on the train and says he married Francey. Peter and Francey sleep in the observation car. Peter hasn't told his father, and so Francey goes with Keith. Peter is greeted by his fiancé Helen (Frances Mercer) and his father (Charles Coburn), who complains he let Keith bring the blonde. Keith brings Francey a wedding cake. Peter calls Francey and is jealous. Peter argues with his father, who won't let him discuss Francey. Peter has Keith bring Francey to the prom, and he gets her in as a student. Francey meets Peter's mother Martha (Beulah Bondi) in the Ladies room. Francey and Peter dance and quarrel. Francey and Helen slap each other. Peter gets his father, and they see Francey fighting with Helen. Keith sees Francey hit Mr. Morgan and dances with Martha. Keith has Francey and Peter sleep with wedding-cake figures.
Mr. Morgan tells Keith to get Francey out of town, but Keith puts her in Peter's botany class, where amorous Francey gets attention. Culpepper (Grady Sutton) tries to help Francey. Peter tells Francey to get them an apartment. The manager (Franklin Pangborn) won't allow Peter in Francey's apartment. So they go to a boathouse, which is occupied. Peter tells his father before his speech that Francey is his wife. Mr. Morgan stops his speech and tells Peter not to tell Martha. Francey says good-bye to Peter, but he climbs in her window to tell her not to leave. Francey kisses Peter good-bye. She delays and decides to stay. Francey puts off the manager while Peter climbs down the fire escape. Helen sees Peter and tells Martha, who goes to Francey and learns they are married. Martha tells Francey she has heart trouble when her husband yells. Keith comes in and shows Martha how Francey dances. Mr. Morgan arrives to see all three dancing. He says Francey must divorce, or Peter must resign. Martha rebels against her husband.
Keith goes to Peter's class and says Francey is leaving. Peter drinks alcohol. Mr. Morgan brings to Peter's class a millionaire, who laughs at drunk Peter and promises a library. Peter tells his father he is quitting because his wife is more important and then passes out. Francey leaves on the train, crying, and so does Martha. The porter (Willie Best) is influenced by their moods as they discover each other. Peter and his father get the train to stop and come aboard. Peter gets his father to reconcile with Martha, and Peter joins Francey at last in a private room.
This comedy plays upon the tension that exists until Peter and Francey can consummate their marriage. The haughty attitude of Mr. Morgan is exposed, because his wife has to feign heart trouble in order to subdue his temper.