Two jilted lovers decide to marry each other with detachment and are tested by their former lovers getting divorces and coming back.
On a ship Steve Porter (Pat O'Brien) tells Jeff Hunter (John Halliday) and guys how much he likes Elaine. Steve goes to Elaine (Myrna Loy), who says she is married. Steve gets drunk and finds Jeff. Mary (Irene Dunne) says good-bye to Aubrey (Lester Vail), who is getting married even though they love each other. Jeff tells Steve to find someone else and points to stranger Mary. Jeff leaves, and Steve talks to her. They learn they are in similar situations. Steve borrows a car, and police arrest them. Jeff gets them out and takes them to her shop. Steve accepts a job on Jeff's paper. Steve finds Mary at a piano singing a love song, and he returns her Romeo and Juliet. Mary goes with Steve to a dog show.
Steve and Mary get married. In their home Mary gets a clock from Aubrey, and Steve reads the card saying he misses her. Mary and Steve have a pillow fight. Elaine in Algiers writes to Steve she is being divorced and is going to London to see him. Steve tells Jeff, who finds Mary home alone. Jeff fires Steve to keep him from going to London. Steve comes home to Mary, who says she is going to have a baby. He says he lost his job. In the hospital Mary shows her baby to Steve.
On their third anniversary Steve gets a telegram that Elaine is arriving and tells Mary. He says he is going to a barber, and Aubrey calls on Mary, saying it didn't work out. Aubrey says he is going to Vienna and asks her to go with him. Mary says she couldn't take the baby away from Steve. Mary tells her maid Kate to pack her bag, writes a good-bye note to Steve, and leaves with Aubrey. Steve calls Elaine. Aubrey stops Mary from calling, and she tells him she is going home. Jeff and the Colonel (Matt Moore) wait with the note for Steve as Mary rushes to see her baby. Mary tells them she is very happy. Steve comes home, and Jeff reminds him it is his anniversary, giving him flowers for Mary. Steve announces he is going to see Elaine; but they all agree that Jeff and the Colonel can bring her there. Mary greets Elaine and watches her put on makeup as Elaine assumes that Steve and Mary are not in love. Mary tells Steve that Elaine is beautiful, and Elaine tells Steve that Mary understands. Mary cries and tells Jeff that she realizes now how much she loves Steve while Jeff implies he likes her. Elaine asks Steve to kiss her, and he says they are just good friends. Steve tells Elaine about his baby. Steve tells Mary that he was blind and is crazy about her. They kiss.
This romantic drama makes sense, because the two disappointed lovers remain true to each other while the partners that jilted them end up divorced and rejected by their former lovers too.