The Fat Man is a 1951 American film noir crime film directed by William Castle. It is based on a radio drama of the same name, with J. Scott Smart reprising his role as Brad Runyan, a portly detective. The cast includes Rock Hudson and Julie London. Originally released by Universal Pictures, the film is now in the public domain. William Castle later called it "a potboiler of little merit, except that I was able to cast Rock Hudson... and to use Emmett Kelly, the Ringling Brothers clown, as the villain."