Despite her mother's objections, the naive young daughter of a show boat captain is thrust into the limelight as the company's new leading lady.

Doctor Hugo Hackenbush, Tony, and Stuffy try and save Judy's sanitarium by winning a big race with a finicky horse owned by Judy's boyfriend Gil. There are a few problems. Hackenbush, who was recently put in charge of the sanitarium, isn't really a doctor, he's a veterinarian.

Jim "Lucky" Moore, an insurance salesman, comes up with a novel policy for his friend, Steve: a 'love insurance policy', that will pay out $1-million if Steve does not marry his fiancée, Cynthia. The upcoming marriage is jeopardized by Steve's ex-girlfriend, Mickey, and Cynthia's disapproving Aunt Kitty. The policy is underwritten by a nightclub owner, Roscoe, who sends two enforcers - Abbott and Costello - to ensure that the wedding occurs as planned.

Boisterous teen Judy Bellaire is expelled from her all-female boarding school for convincing her fellow school chorus members to sing a classical piece with a modern swing beat. She returns to her dysfunctional home, dejected, but, with the encouragement of her family's cook, Judy decides to follow her dream and audition for a Broadway musical.

Nina Maria Azara is the beautiful and alluring singing spy for Spain during the Napoleonic Wars. Her mission is to seduce French officers, in order for them to reveal Napoleon's intentions toward Spain. She is sent to Bayonne, France to gather military secrets. Prior to this, she meets Don Diego while performing at a club. Unknown to her, Don Diego is actually Captain Andre, who is sent to Spain to spy on her. While in France, Nina discovers Diego's true identity, only after she has fallen in love with him. Nina Maria outwits her potential captors, returns to Spain and goes into hiding. Napoleon's troops invade Spain, resulting in Nina's capture. In a strange twist of fate, Nina and Captain Andre are reunited, but the 2 nations are now at war...

The Marx Brothers take on high society and the opera world to bring two lovers together. A sly business manager and two wacky friends of two opera singers help them achieve success while humiliating their stuffy and snobbish enemies.

An incognito opera singer falls for a policeman who has been assigned to track down her fugitive brother.

Bill Burnett, a resident of Bali, visits New York City, meets and falls in love with Gail Allen, the successful manager of a Fifth Avenue shop, who is determined to remain free and independent. Bill proposes, Gail declines and Bill goes home to Bali. But a young girl, Rosie, and Tony the Window Cleaner, who dispels advice on every floor, soon have Gail thinking maybe she was a bit hasty with her no to Bill's proposal. Ere long she discovers that she does love Bill and can't live without him. She goes down to Bali to give him the good news. He learns that he is soon to marry Noel Van Ness. She goes back to New York City.

Actor Lee Tracy presides as ringmaster over a show that combines the best elements of cinema with the circus, what he calls a Cinema Circus. Tracy introduces a number of professional circus acts, plus a cavalcade of movie stars who have side shows under the open air big tent. There is as much action in the audience as Tracy identifies a number of movie stars watching the proceedings incognito, having their own fun in the stands, and sometimes interacting with the circus acts.

A talented baseball player discovers he can only sing beautifully when he has a cold, leading a nightclub manager to hilariously attempt to keep him sick while featuring a host of musical performances.