In a Manhattan bar short-sighted millionaire Elisha Whitney meets his assistant Billy Crocker who has organised his boss's transatlantic trip. Reno Sweeney, a club singer, arrives angrily as Billy has stood her up, and Billy admits to her that he loves another.

The S.S. American is about to set sail and Billy arrives just in time to deliver Whitney's passport. Evangeline Harcourt, an old flame of Whitney's is also on board with her daughter, Hope, and Hope's fiance, Sir Evelyn Oakliegh. They plan to marry on board. This news is devastating for Billy as it is Hope that he secretly loves. In desperation he stows away.

Also on board are two more stow aways, world renound gangster Moonface Martin, and his moll, Erma. They help Billy out with a fake passport, and also steal Whitney's glasses so that he cannnot discover Billy's presence on board. As Billy and Moonface work there way through a number of disguises to prevent capture, Reno falls for Sir Evelyn.

Billy and moonface are caught, but Billy has Moonface's passport, and instead of being locked up he is used to satisfy the passengers hunger for celebrities as the ships biggest star.

When Reno puts on a show for the passengers, she asks for those present to confess their sins. Sir Evelyn, to Hope's horror, confesses to a fling with a chineese girl, and Billy confesses his true identity. He and moonface are locked up.

Two chineese converts are also locked away for gambling, and Billy and Moonface, after a quick game of strip poker, steal their cloths and escape. They arrive at the wedding in disguise and manage to break it up. A quick switch around and a triple wedding takes place instead with Hope and Billy, Reno and Evelyn and Evangeline and Whitney getting married.