The Secret of the Whistler is a 1946 American mystery film noir based on the radio drama The Whistler. Directed by George Sherman, the production features Richard Dix, Leslie Brooks and Michael Duane. It is the sixth of Columbia Pictures' eight "Whistler" films produced in the 1940s, all but the last starring Dix.

Plot: An artist married to a wealthy but ill woman begins an affair with one of his models, who is after him solely for his money. His wife discovers the affair and threatens to cut him out of her will. In order to be able to keep both the wife's money and his girlfriend, he begins to secretly poison his wife - but events take a surprising turn after she eventually dies.