Arriving in New York to meet his Aunt Adeline, now resident there, before taking a short holiday, Sam Marlowe finds his cousin Eustace about to marry a wealthy local girl, Billie. Adeline soon puts a stop to her son's intentions, and orders him back to England with Sam a few short days later.

Boarding a liner back to Southampton, Sam is almost immediately spellbound by a beautiful young woman he sees embarking as a fellow passenger. As the journey progresses he concocts further reasons to meet with her - and eventually discovers that she is, in fact, Bille Bennett, his cousin's former-betrothed.

Sam is soon madly in love, and Billie similarly keen on him. Unfortunately, he's not been wholly honest about his interests, and plied Eustace for information so that he can make out that they have more in common. She dreams of meeting a real alpha male - her own Sir Galahad - and unfortunately for Sam, he doesn't really fulfil the criteria.

Eustace, meanwhile, is confined to his bed with terrible sea-sickness. When he discovers his cousin's antics he is understandably outraged, but on an attempt to leave his cabin, runs into a rather bold woman he passed on the New York subway - a very macho woman, complete with elephant gun, who is longing for a man she can dominate. He fits the bill entirely!

Sadly for Sam, his romantic entanglement with Billie does not run nearly as smooth. He's shown up as being unable to swim when she falls in the ship's pool, and thereafter announces her engagement to her friend and fellow passenger Bream, who's had his eye on her since she was engaged to Eustace.

Arriving in Southampton, Sam is downbeat until he spots an opportunity to keep Billie in England, and soon hatches a plan to win her round. However, a gun, a dog-napping, a suit-of-armour and his Aunt's vacant home do not prove as simple to manage as he had hoped.