Four explorers are summoned to Peru by the brilliant physicist Dr Thorkel. They discover a rich source of radium and a half-mad Thorkel who shrinks them down to one-fifth their normal size when they threaten to stop his unorthodox experimentation.
Unfortunately the movie Dr. Cyclops is not yet available on Disney Plus.
| Directing | Ernest B. Schoedsack | Director |
| Writing | Malcolm Stuart Boylan | Screenplay |
| Writing | Tom Kilpatrick | Screenplay |
| Production | Merian C. Cooper | Producer |
| Production | Dale Van Every | Producer |
| Sound | Gerard Carbonara | Original Music Composer |
| Camera | Henry Sharp | Director of Photography |
| Editing | Ellsworth Hoagland | Editor |
| Art | A. E. Freudeman | Set Designer |
| Production | William LeBaron | Executive Producer |
| Art | Hans Dreier | Art Direction |
| Art | A. Earl Hedrick | Art Direction |
| Art | Robert Odell | Art Direction |
| Costume & Make-Up | Charles Gemora | Makeup Artist |
| Directing | Hollingsworth Morse | Assistant Director |
| Sound | Harry Lindgren | Sound Recordist |
| Sound | Richard Olson | Sound Recordist |
| Sound | Albert Hay Malotte | Original Music Composer |
| Sound | Ernst Toch | Original Music Composer |
