Louisa Carmichael dreams not of glittering ballgowns, but of exploring the tropical waters of the Caribbean with her latest invention, an underwater breathing apparatus.

Lord Rupert Haywood, future Duke of Belmonte, has no desire to manage an estate with his corrupt father. He prefers to roam the ocean with his crew of rugged pirates.
When her mother arranges a marriage for her, Louisa decides she might just don a pair of breeches and discover the Caribbean in disguise. The only problem is a certain very handsome captain...