Directed by
| Walter Summers | ||
Writing Credits
| Edgar Wallace | ... | (novel) |
| Patrick Kirwan | ... | (screenplay) & |
| Walter Summers | ... | (screenplay) & |
| John Argyle | ... | (screenplay) (as J.F. Argyle) |
| Jan Van Lusil | ... | (additional dialogue) (as Jay Van Lusil) |
Cast (in credits order) verified as complete
| Bela Lugosi | ... | Dr. Feodor Orloff / John Dearborn | |
| Hugh Williams | ... | Det. Insp. Larry Holt | |
| Greta Gynt | ... | Diana Stuart | |
| Edmon Ryan | ... | Lt. Patrick O'Reilly | |
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Wilfred Walter | ... | Jake (as Wilfrid Walter) |
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Alexander Field | ... | Fred Grogan |
| Rest of cast listed alphabetically: | |||
| O.B. Clarence | ... | Prof. John Dearborn (voice) (uncredited) | |
| May Hallatt | ... | Police Constable Griggs (uncredited) | |
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Bryan Herbert | ... | Police Sgt. Walsh (uncredited) |
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Arthur E. Owen | ... | Dumb Lou (uncredited) |
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Charles Penrose | ... | Morrison - Undercover Detective (uncredited) |
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Gerald Pring | ... | Henry Stuart (uncredited) |
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Philip Stewart | ... | Scotland Yard Detective (uncredited) |
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George Street | ... | Scotland Yard Commissioner (uncredited) |
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Julie Suedo | ... | Orloff's Secretary (uncredited) |
Produced by
| John Argyle | ... | producer |
Music by
| Guy Jones | ||
Cinematography by
| Bryan Langley | ... | (photography) |
Editing by
| Ted Richards | ... | (as E.G. Richards) |
Art Direction by
| Duncan Sutherland | ||
Production Management
| Hamilton G. Inglis | ... | production manager (as H.G. Inglis) |
Second Unit Director or Assistant Director
| Jack Martin | ... | assistant director |
Sound Department
| Harry Benson | ... | recording supervisor (as H. Benson) |
| A.E. Rudolph | ... | sound recordist |
Camera and Electrical Department
| Ronald Anscombe | ... | camera operator |
Music Department
| Guy Jones | ... | music arranger |
| C. King Palmer | ... | composer: organ music |
Additional Crew
| George Collins | ... | production assistant |
