Adapted from the operetta by Rida Johnson Young, an opera singer agrees to marry her mentor but then falls in love with a baritone.
At a May festival Kip (Tom Brown) tells elderly Marcia Morney (Jeannette MacDonald) that Barbara is auditioning for opera. Marcia remembers and sees Kip and Barbara (Lynne Carver) break up over her career. Barbara cries and tells Marcia that she wants to be a singer. To show she understands, Marcia tells Barbara her story.
In the court of Louis Napoleon (Guy Bates Post) young Marcia arrives with Nicolai Nazaroff (John Barrymore) and sings. Nicolai gets Trentini (Paul Porcasi) to write an opera for Marcia. She thanks Nicolai and agrees to marry him. Marcia goes out in a carriage at 3 a.m. and hears singing. Paul Allison (Nelson Eddy) sings a student drinking song and is glad to meet the American Marcia. He insists that she promise to come to lunch. Paul sings "Virginia Ham and Eggs." Paul tells his teacher August Archipenko (Herman Bing) that Marcia is coming. Marcia returns home to find Nicolai asking her to explain. Paul steals two tickets to the opera from his friend Fanchon (Sig Ruman). Paul and August break both plates, but Marcia helps cook ham and eggs. Paul sings "Carry Me Back to Old Virginny" with Marcia. August gets Marcia to encourage Paul to work on opera; but she tells Paul not to see her again.
Paul and August attend the opera to hear Marcia sing the "Page's Aria." Fanchon forces Paul and August to give up the seats. In her dressing-room Paul praises Marcia and invites her to a May fair. She accepts so that he will leave. At the fair they have fun and dance. Paul sings "Sweetheart, You Will Remember" to Marcia and kisses her. She says she is going to marry Nicolai and recounts what he has done for her.
Seven years pass as Nicolai helps Marcia practice and sing operas. Marcia and Nicolai arrive in America. Marcia is discontent, and Nicolai says he loves her too much but does not possess her. Nicolai tells the opera men that Marcia will not do Traviata but the opera Trentini wrote for her. Nicolai tells Marcia that Paul will sing Petrov. At rehearsal August thanks Marcia for having encouraged Paul, making Nicolai suspicious. In the opera the duets between Marcia and Paul are dynamic, and they kiss. Paul says he will take her away that night. Marcia sends Ellen (Rafaela Ottiano) to tell Paul that Marcia will see him in the morning. Nicolai congratulates Marcia for "living emotion." Nicolai and Paul thank each other. Marcia tells Nicolai that she made a mistake in leaving Paul and that she loves him. Nicolai says he won't stand in her way. Marcia sees that Nicolai left with a gun and follows him in the snow. Nicolai goes to Paul's flat and shoots him. Marcia comes in and holds Paul as he dies.
Old Marcia tells Barbara that is why she lives alone and tells her to think of Kip. Kip apologizes to Barbara, who says she is not going to New York; they kiss. Marcia dies, and the spirits of Paul and Marcia sing "Sweetheart."
Music lovers will enjoy this romantic operetta. Marcia persuades Barbara to give up her career for Kip. Yet Marcia could have had both if she had not made the mistake of confusing the two by marrying Nicolai out of gratitude.