นักแสดง
Arthur Space
Mr. North
Jimmy Lloyd
FBI Agent Alison
Ray Teal
Police Sergeant
Steve Pendleton
Police Detective Gaines
Lee Phelps
Charles Evans
Dr. Homer Allen
Tamara Shayne
Mrs. Ecko, the Landlady
Art Baker
Dr. Frederick Townsend
Reed Hadley
Narrator (voice)
William Tannen
FBI Chemist
Gale Storm
Voice on Tape Recorder
Myron Healey
FBI Agent Thompson
John Hamilton
G.W. Hunter
Howard Negley
Feodore
Marten Lamont
Arthur Tovey
Louis Hayward
Philip 'Scotty' Grayson
Raymond Burr
Krebs
Philip Van Zandt
Anton Radchek
Keith Richards
FBI Agent Miller
Louise Allbritton
Dr. Anastasia 'Toni' Neva
Carl Esmond
Dr. Ritter von Stolb
Onslow Stevens
Igor Braun
Lowell Gilmore
Dr. William Forrest
Suzanne Ridgway
Paul Bryar
Crane Whitley
Dennis O'Keefe
Daniel F. O'Hara
Frank Ferguson
Carl Bemish