Giants Mollusks are released from the earth by an earthquake and start killing people.
| Writing | David Duncan | Story |
| Directing | Arnold Laven | Director |
| Production | Arthur Gardner | Producer |
| Camera | Lester White | Director of Photography |
| Art | Rudy Butler | Set Decoration |
| Production | Kerwin Coughlin | Casting |
| Production | Jules V. Levy | Producer |
| Crew | Augie Lohman | Special Effects |
| Editing | John Faure | Editor |
| Writing | Pat Fielder | Screenplay |
| Sound | Heinz Roemheld | Original Music Composer |
| Art | James Dowell Vance | Art Direction |
| Camera | Scotty Welbourne | Underwater Director of Photography |
| Crew | Norman Bishop | Technical Supervisor |
| Sound | Charles Althouse | Sound Mixer |
| Directing | Paul Stader | Other |
| Costume & Make-Up | Abe Haberman | Makeup Artist |
| Crew | Ted Haworth | Other |
| Crew | Robert H. Crandall | Other |
| Camera | Paul Eagler | Other |
| Sound | B. F. Remmington | Sound Recordist |
| Sound | Heinz Roemheld | Music Director |
| Costume & Make-Up | Olga Collings | Hairstylist |
| Directing | Maurice Vaccarino | Assistant Director |
| Costume & Make-Up | Allen Sloane | Wardrobe Supervisor |
| Sound | Heinz Roemheld | Conductor |
| Production | Virginia Mazzuca | Production Assistant |
| Sound | Charles Althouse | Sound Recordist |
| Sound | Joel Moss | Sound Recordist |
