With the cyclotram, an atomic-powered rock-boring vehicle, Dr. Jerimiah Morley leads an expedition into a subterranean world.
You can now watch Unknown World online on the following streaming providers in the United States.
| Directing | Terry O. Morse | Director |
| Writing | Millard Kaufman | Screenplay |
| Production | Irving Block | Producer |
| Production | Jack Rabin | Producer |
| Sound | Ernest Gold | Original Music Composer |
| Camera | Henry Freulich | Director of Photography |
| Camera | Allen G. Siegler | Director of Photography |
| Editing | Terry O. Morse | Editor |
| Art | Irving Block | Production Design |
| Art | Jack Rabin | Production Design |
