Bunco Squad (1950)

Told in semi-documentary style, this film deals with a little-known section of the Los Angeles Police Department which is assigned solely to checking on the activities of fortune tellers, swamis, palmists, and other occult societies, missing only Sciencetology. The primary story has L.A. police detectives Steve Johnson and 'Mack' McManus tracking down a wave of suicides they think have been influenced by swindler-murderer Anthony Wells, who runs a pretentious house staffed with occultists across the board and is trying to embezzle from Jessica Royle, a wealthy widow whose son was killed in action in World War II. Johnson uses his actress fiancee Grace Bradshaw as an undercover operative to get inside information.