The Purple Cipher (1920)
Genres: Mystery, Silent
Cast: Earle Williams, Vola Vale
The Purple Cipher is a 1920 American silent mystery film directed by Chester Bennett and starring Earle Williams, Vola Vale and Ernest Shields. Shot by Vitagraph at the company's Brooklyn studios, it was based on the short story The Purple Hieroglyph by Murray Leinster. The story was adapted twice more in the sound era as Murder Will Out (1930) and Torchy Blane in Chinatown  (1939).