Herman Bahr's German play The Yellow Nightingale from 1907 became Paramount's 1938 entry in the then-popular operetta cycle. Gladys Swarthout, formerly of the Met, stars as Ilona Boros, a peasant girl with a magnificent voice who becomes a pawn in the rivalry between opera tenor Tony Kovach (John Boles) and his business manager Zoltan Jason (John Barrymore). Both men are infatuated with the beautiful, but cold, Countess Foldessy (Claire Dodd), and Tony plans to make Ilona a star so that Jason will be attracted to her instead. The scheme backfires, of course, and soon both men are fighting over Ilona, the outraged countess left to instead pursue Jason's butler, Von Hemisch (Curt Bois).

In between the comedy, Swarthout, Boles, and company perform such well-known selections as "Because," from the opera Jocelyn; "Habanera," from Carmen; "La Ci Darem la Nano," from Don Giovanni; and Ralph Rainger and Leo Robin's "Tonight We Love."