Esther Williams stars in this dramatic true musical romance of turn-of-the century swimming champion Annette Kellerman, better known as the Million Dollar Mermaid. As a child in Australia, Kellerman learns to swim to overcome a potentially crippling physical handicap and develops into a champion. As a young woman, she travels with her father to London and dreams of a career as a dancer. But when her father falls on hard times, Kellerman resorts to her aquatic talents: swimming 30 miles of the Thames in a famous publicity stunt, then shocking Boston by appearing in a one-piece suit.