The Unguarded Moment is a 1956 American crime film noir thriller film directed by Harry Keller and starring Esther Williams, George Nader, John Saxon, and Edward Andrews.

Esther Jane Williams was an American competitive swimmer and actress. She set regional and national records in her late teens on the Los Angeles Athletic Club swim team. Unable to compete in the 1940 Summer Olympics because of the outbreak of World War II, she joined Billy Rose's Aquacade, where she took on the role vacated by Eleanor Holm after the show's move from New York City to San Francisco. While in the city, she spent five months swimming alongside Olympic gold-medal winner and Tarzan star Johnny Weissmuller. Williams caught the attention of Metro-Goldwyn-Mayer scouts at the Aquacade. After appearing in several small roles, and alongside Mickey Rooney in an Andy Hardy film and future five-time co-star Van Johnson in A Guy Named Joe, Williams made a series of films in the 1940s and early 1950s known as "aquamusicals", which featured elaborate performances with synchronised swimming and diving.