The Master Mystery is a 1918 American mystery silent serial film told in 15 installments. The film was directed by Harry Grossman and Burton L. King and written by Arthur B. Reeve and Charles Logue. The film stars Harry Houdini, Marguerite Marsh, Ruth Stonehouse, Edna Britton, William Pike, and Charles Graham. Episode 1 was released on November 18, 1918, by Octagon Films.

Plot
Justice Department agent Quentin Locke is investigating a powerful cartel that is protected by The Automaton, a robot. However, it uses a gas weapon known as The Madagascar Madness.

Episodes
1. Living Death
2. The Iron Terror
3. The Water Peril
4. The Test
5. The Chemist’s Shop
6. The Mad Genius
7. Barbed Wire
8. The Challenge
9. The Madagascan Madness
10. The Binding Ring
11. The Net
12. The Death Noose
13. The Flash of Death
14. The Tangled Web
15. Bound at Last; or, Unmasking of the Automaton

Cast
Harry Houdini as Quentin Locke
Marguerite Marsh as Eva Brent
Ruth Stonehouse as Zita Dane
Edna Britton as De Luxe Dora
William Pike as Paul Balcom
Charles Graham as Herbert Balcom
Floyd Buckley as Q the Automaton
Jack Burns as Peter Brent