The Unholy Three is a 1930 American Pre-Code melodrama directed by Jack Conway and starring Lon Chaney. Its plot involves a crime spree. The film is a sound remake of the silent 1925 film of the same name, with both films based on the novel The Unholy Three, by Tod Robbins.

In both versions, the roles of Professor Echo and Tweedledee are played by Lon Chaney and Harry Earles respectively. This film is notable for the fact that it was Chaney's last film, as well as his only talkie. Chaney died from throat cancer one month after the film's release.