A French opera singer without a passport joins an American jazz band on a ship and hides out with them in this musical comedy.
In Paris Nikki Monet (Lily Pons) walks out of her wedding, leaving the wealthy opera patron Paul de Vry (Gregory Gay). She trades her wedding dress to a country woman and hitches a ride with musician Windy (Gene Raymond), helping him fix a flat tire. She reads his palm and sings. Windy drives her to Paris, where he dumps her.
Windy and his jazz band board a ship, and Whammo (Jack Oakie) sings "Love and Learn." Nikki stows away in their room and says she'll sing; but the captain locks her up and fines the band. At port Nikki jumps out the window, and the band finds her in their bedroom. They hide her from Immigration. To get her to leave the four men undress; but, afraid the police will catch her, they bring her back. She sleeps on the couch, and Whammo takes her a blanket. She sings "Seal It with a Kiss." When she says she's leaving, they give her the bedroom. Whammo cooks, and Frank (Frank Jenks) irons. Claire Williams (Lucille Ball) comes in and kisses Windy, who says that Nikki is the wife of Butch (Mischa Auer). Hammacher (Herman Bing) offers them $40 plus room and board to play at his roadhouse.
Hammacher shows Claire her room, and each man dances with Nikki. During a group photo Nikki puts soap on Claire's shoes. Whammo sings "Moon Face." Claire while dancing keeps slipping and falling, and she quits. Nikki offers to sing and sings "The Blue Danube." She gets Hammacher to increase their salary. Claire sees Windy with Nikki and talks to a reporter, who calls the police. Windy and the band sing "My Nephew from Nice." When the police arrive, Nikki and the band escape. Windy learns that Claire informed on Nikki. The four cut the cards to see who will marry Nikki. Whammo wins but yields to Windy, who proposes. They are about to wed when Nikki learns that they cut cards for her. She runs off and is arrested.
Paul gets Nikki into an opera, and they plan to wed. Hammacher gets the four out of jail, and they dress to attend the opera. Whammo locks Hammacher in a closet, as Whammo, Frank, and Butch plan to disrupt Nikki's aria with noisemakers. Windy frees Hammacher, and they go to stop the others. Nikki sings "Una Voce Poco Fa," while Whammo throws spit wads at the conductor; but Whammo stops the others until the applause. The band learns that Nikki paid their fines. Whammo, Frank, and Butch tie and gag Windy and go to Nikki's wedding to persuade her that Windy loves her. Nikki runs out to the car, where she weds the gagged Windy.
This amusing comedy offers both operatic and jazz music, while laws on national borders, jealousy, and misunderstanding keep the plot moving.