RELEASE DATE: August 16, 1925. MOVIE TITLE: The Unholy Three. STUDIO: Metro-Goldwyn-Mayer (MGM). PLOT: Three sideshow performers leave their lives of captivity and become ''The Unholy Three.'' Echo the ventriloquist assumes the role of a kindly old grandmother who runs a bird shop. Tweedledee, the ''twenty inch man,'' becomes her grandbaby, and Hercules is their assistant. Soon an incredible crime wave is launched from their little store. PICTURED: LON CHANEY as Professor Echo, MAE BUSCH as Rosie O'Grady and MATT MOORE as Hector MacDonald.