Continuity mistake: When Harpo is playing Russian Roulette, one of the villains claims that the gun has "four bullets" in it. One shot is fired at Harpo, and four by him, totaling five shots.
Continuity mistake: When Sinatra comes down to Esther Williams to serenade her by the pool, she has just been swimming. When she meets up with him by the tree she is dry as a bone. Even her swimsuit is dry.
Continuity mistake: The movie begins with Joe Backett witnessing one of the many victories by swim star Eve Barrett. In the very first wide shot of the pool, Esther Williams is fitting her cap getting ready to compete. Cuts to a closer view, and she has a towel on her shoulders that she has to take off before fastening her cap. (00:01:45)