The action takes place on the SS AMERICAN, sailing from New York to England. On board are the beautiful American heiress Hope Harcourt, her English fiancé Sir Evelyn Oakleigh and Hope's mother. Stowing away on board is Billy Crocker, a young admirer of Hope'0 who can't believe she would really marry the silly S1r Evelyn and determines to try and stop her. Public Enemy Number Thirteen, with his moll Bonnie, is also along for the ride and he passes on to Billy the passport and ticket of a gangster friend of his who didn't catch the boat. This leads, to unwelcome complications for Billy as he and the Public Enemy have to keep changing disguises to avoid arrest. Keeping the steam at boiling point in the ship's engine room arid working the stabilisers overtime is sexy, incandescent Reno Sweency, ex-evangelist and currently right club singer, With her help all the shipboard disasters are averted and all the romances sorted out including her own.