The S.S. American is preparing to set sail from New York to England. Billy Crocker, a young assistant to Wall Street tycoon Elisha J. Whitney, a passenger on the ship, decides to stow away in hopes of wooing his long-lost love and wealthy debutante, Hope Harcourt, who is also on board. However, much to Billy’s chagrin, Hope’s mother, Evangeline Harcourt, is delighted that Hope is engaged to be married to a stuffy Englishman, Lord Evelyn Oakleigh (who is also onboard), upon arrival in England.

Also on the ship are Reno Sweeney, an evangelist-turned-nightclub singer, and her bevy of “angelic” showgirls, who will be providing music and dance entertainment during the crossing. The ship has no sooner set sail than Reno runs into Billy, an old friend, and he persuades her to help him break up  Hope’s engagement.

“Moonface” Martin, a gangster known as “Public Enemy 13” and his moll Erma are disguised as a reverend and a missionary, respectively. They have two Chinese “converts” and all four attempt to evade the law while on board. Billy eventually learns the identity of this misfit bunch, and, in exchange for his silence, they too join in the scheme to break up Hope and Lord Evelyn.

After more disguises, ploys, confessions, mistaken identities, and marriage proposals, all done to the fantastic music of Cole Porter, how will everything work out? Who knows? Anything goes!