A bride and groom are inexplicably prevented from attending their wedding by their exact doubles, who then marry. Six years later, Tom and Gerry Jeffer's Park Avenue apartment manager shows their apartment to prospective tenants while they are still in residence because they are behind in rent. An elderly sausage manufacturer, known as the "Wienie King," who is looking at the apartment is so smitten by Gerry that he gives her $700 to pay all the bills. Gerry is tired of being broke and is doubly frustrated because Tom, a struggling architect, has continually rejected her attempts to use her beauty to get financial backers for his projects. Although she is still in love with Tom, Gerry so firmly believes that she has held her husband back that she leaves him, despite his earnest efforts to deter her. At Pennsylvania Station, Gerry uses her feminine wiles to get The Ale and Quail Club, a men's hunting club that has reserved an entire car, to buy her a ticket on the train headed for Palm Beach, Florida. The Club proves too rowdy, however, and after the men shoot out the windows she escapes into a sleeper car, where she accidentally breaks John D. Hackensacker III's spectacles while climbing into the upper berth. In the morning, Gerry discovers that the conductors have disconnected the Club's car because of their unruliness and have thereby left her without her suitcase. John, one of the wealthiest men in the world, takes an interest in Gerry and disembarks with her in Jacksonville, Florida. There the normally frugal multimillionaire takes pleasure in buying Gerry an entire wardrobe of extravagant clothes and a ruby bracelet. Gerry is thrilled when she discovers she has made the acquaintance of one of the richest men in the world, and accompanies him on his yacht to Palm Beach. When she sees Tom waiting at the dock for her, Gerry introduces him as her brother, "Captain McGloo." John's sister, the much-divorced Princess Maud Centimillia, who is ready to discard yet another suitor, Toto, immediately makes advances toward Tom. Gerry and Tom stay at the Hackensacker mansion, and while John woos Gerry, Maud woos Tom. Gerry, meanwhile, successfully interests John in becoming a financial backer of Tom's plans for a suspended airport. One evening, John, who has fallen in love with Gerry, serenades her underneath her balcony to the accompaniment of an orchestra, not realizing that he is providing the romantic background for Gerry and Tom to reunite. The next morning, Gerry gently rejects John's marriage proposal and reveals to a stunned John and Maud that she and Tom are not brother and sister, but are husband and wife. Always pragmatic, John vows to fulfill his commitment as a backer for Tom's project, and he and Maud are delighted when they learn that Tom and Gerry have twin siblings. A joint marriage soon takes place.