- Warren Hull
- Richard Wentworth / The Spider / Blinky McQuade
- Mary Ainslee
- Nita Van Sloan
- Dave O'Brien
- Jackson, Wentworth's Aide
- Joseph W. Girard
- Police Commissioner Kirk
- Kenne Duncan
- Ram Singh, Wentworth's Hindu Chauffeur
- Corbet Morris
- McLeod
- Bryant Washburn
- Westfall
- Charles Miller
- Mr. Van Sloan
- Anthony Warde
- Henchman Trigger
- Harry Harvey
- Stephen
- Arthur Belasco
- Butler
- Stanley Blystone
- Policeman
- Lane Chandler
- Police Lab Fingerprint Man [Ch. 14]
- Stephen Chase
- Jenkins, Wentworth's Butler
- George Chesebro
- Henchman
- Steve Clark
- Henchman Meeker [Chs. 2, 3]
- Ruth Findlay
- Secretary
- Jack Gardner
- Poppy - the Bartender
- Chuck Hamilton
- Henchman Gunther
- Tom London
- Detective [Ch. 13]
- George Magrill
- Henchman
- Joe McGuinn
- Henchman
- Irving Mitchell
- Holden
- Jack Mulhall
- Detective Farrell [Chs. 13, 14, 15]
- Frank O'Connor
- Detective [Ch. 10]
- Jack O'Shea
- Armored Car Driver [Ch. 3]
- Jack Perrin
- Armored Car Guard [Ch. 3]
- Lee Phelps
- Police Officer Mulligan
- Jack Roper
- Detective [Ch. 13]
- Cy Schindell
- Henchman Brown [Ch. 1]
- Charles Sullivan
- Henchman Haney
- Forrest Taylor
- Voice of The Gargoyle
- Ken Terrell
- Henchman
- Michael Vallon
- Henchman
- Dale Van Sickel
- Henchman Cahill
