Directed by
| Curt Siodmak | ... | (directed by) |
| Herbert L. Strock | ... | (uncredited) |
Writing Credits
| Curt Siodmak | ... | (screenplay by) and |
| Ivan Tors | ... | (screenplay by) |
Cast (in credits order) verified as complete
| Richard Carlson | ... | Dr. Jeffrey Stewart | |
| King Donovan | ... | Dr. Dan Forbes | |
| Jean Byron | ... | Connie Stewart | |
| Harry Ellerbe | ... | Dr. Allard | |
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Leo Britt | ... | Dr. Benton |
| Leonard Mudie | ... | Howard Denker | |
| Byron Foulger | ... | Mr. Simon | |
| Michael Fox | ... | Dr. Serny | |
| John Zaremba | ... | Chief Watson (as John Zarimba) | |
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Lee Phelps | ... | City Engineer |
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Watson Downs | ... | Mayor |
| Roy Engel | ... | Gen. Behan (as Roy Engle) | |
| Frank Gerstle | ... | Col. Willis | |
| John Vosper | ... | Capt. Dyer | |
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John Dodsworth | ... | Dr. Carthwright |
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Charles Williams | ... | Cabbie (as Charlie Williams) |
| Michael Granger | ... | Kenneth Smith | |
| William 'Billy' Benedict | ... | Albert (as Bill Benedict) | |
| Kathleen Freeman | ... | Nelly | |
| Douglas Evans | ... | Pilot | |
| Strother Martin | ... | Co-Pilot | |
| Jarma Lewis | ... | Stewardess | |
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Elizabeth Root | ... | Joy |
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Juney Ellis | ... | Spinster |
| Rest of cast listed alphabetically: | |||
| Robert Carson | ... | Airline Pilot (uncredited) | |
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Donald Kerr | ... | Nova Scotia Lab Worker (uncredited) |
Produced by
| Ivan Tors | ... | producer (produced by) |
| George Van Marter | ... | associate producer |
Music by
| Blaine Sanford | ... | (music by) |
| Paul Beaver | ... | (uncredited) |
Cinematography by
| Charles Van Enger | ... | director of photography |
Production Design by
| George Van Marter | ... | (production design) |
Art Direction by
| George Van Marter | ||
Set Decoration by
| Victor A. Gangelin | ||
Second Unit Director or Assistant Director
| Richard Dixon | ... | assistant director |
| Maxwell O. Henry | ... | second unit director (as Maxwell Henry) |
| Andrew Marton | ... | second unit director (uncredited) |
| Marty Moss | ... | assistant director (uncredited) |
Sound Department
| Howard Fogetti | ... | sound (as Howard J. Fogetti) |
| Joel Moss | ... | rerecording supervisor (as Joel F. Moss) |
| Bill Naylor | ... | sound effects |
Special Effects by
| Harry Redmond Jr. | ... | special effects director |
| J. Lawrence Cassingham | ... | technical advisor (also designed control center set) (uncredited) |
Visual Effects by
| Jack R. Glass | ... | special photographic effects (as Jack Glass) |
| Eugen Schüfftan | ... | visual effects supervisor (uncredited) |
Camera and Electrical Department
| Bobby Jones | ... | lighting effects (as Robert Jones) |
Editorial Department
| Herbert L. Strock | ... | editorial supervisor |
Music Department
| Paul Beaver | ... | musician (uncredited) |
Script and Continuity Department
| Mary Gibsone | ... | script supervisor (as Mary Whitlock Gibson) |
Additional Crew
| Leonard Baurmash | ... | technical advisor: radiation |
| Michael Fox | ... | dialogue director |
| Maxwell Smith | ... | technical advisor: electronics |
| Ivan Tors | ... | presenter |
| Otto Hunte | ... | deltatron design (uncredited) |
