Underwater deep-sea miners encounter a Soviet wreck and bring back a dangerous cargo to their base on the ocean floor with horrifying results. The crew of the mining base must fight to survive against a genetic mutation that hunts them down one by one.
Unfortunately the movie Leviathan is not yet available on HBO Max.
| Directing | George P. Cosmatos | Director |
| Writing | David Webb Peoples | Story |
| Writing | David Webb Peoples | Screenplay |
| Writing | Jeb Stuart | Screenplay |
| Production | Aurelio De Laurentiis | Producer |
| Production | Luigi De Laurentiis | Producer |
| Production | Charles Gordon | Executive Producer |
| Production | Lawrence Gordon | Executive Producer |
| Sound | Jerry Goldsmith | Original Music Composer |
| Camera | Alex Thomson | Director of Photography |
| Editing | John F. Burnett | Editor |
| Editing | Roberto Silvi | Editor |
| Production | Jane Feinberg | Casting |
| Production | Mike Fenton | Casting |
| Production | Lynda Gordon | Casting |
| Art | Ron Cobb | Production Design |
| Art | Franco Ceraolo | Art Direction |
| Art | Pier Luigi Basile | Supervising Art Director |
| Art | David F. Klassen | Art Direction |
| Art | William Ladd Skinner | Supervising Art Director |
| Art | Bruno Cesari | Set Decoration |
| Art | Robert Gould | Set Decoration |
| Costume & Make-Up | April Ferry | Costume Design |
| Crew | Giorgio De Vincenzo | Post Production Supervisor |
| Production | Lucio Trentini | Production Supervisor |
| Art | Maria Teresa Barbasso | Set Designer |
| Art | Marco Trentini | Set Designer |
| Production | Roberto Malerba | Location Manager |
| Directing | Ceri Evans | Script Supervisor |
| Production | Gabriella Toro | Production Coordinator |
| Sound | Robin Gregory | Sound Mixer |
| Visual Effects | Jon Curtis Price | Creature Design |
| Sound | Nancy Beach | Orchestrator |
| Sound | Jerry Goldsmith | Conductor |
| Sound | Kenneth Hall | Supervising Music Editor |
| Sound | Arthur Morton | Orchestrator |
| Sound | Michael Dittrick | Music Editor |
| Editing | Gillian L. Hutshing | Assistant Editor |
| Editing | Richard Leeman | First Assistant Editor |
| Editing | Aldo Manni | Negative Cutter |
| Costume & Make-Up | Augusto Grassi | Costumer |
| Costume & Make-Up | Yvonne Zarb Cousin | Costumer |
| Camera | Ramón Bravo | Underwater Camera |
| Camera | Phil Barthropp | Underwater Camera |
| Camera | Tony Cridlin | Grip |
| Camera | Federico Del Zoppo | Additional Photography |
| Crew | Giuseppe Maccari | Cinematography |
| Camera | Ernesto Natoli | Assistant Camera |
| Lighting | Fabio Scepi | Electrician |
| Camera | Mike Valentine | Underwater Camera |
| Costume & Make-Up | Bruce Barlow | Special Effects Makeup Artist |
| Costume & Make-Up | Katalin Elek | Makeup Artist |
| Costume & Make-Up | Zoltan Elek | Key Makeup Artist |
| Costume & Make-Up | Marina Marin | Assistant Hairstylist |
| Costume & Make-Up | John Rosengrant | Special Effects Makeup Artist |
| Costume & Make-Up | Aldo Signoretti | Key Hair Stylist |
| Directing | Marco Alberti | Second Second Assistant Director |
| Directing | Matt Earl Beesley | First Assistant Director |
| Directing | Luca Lachin | Second Assistant Director |
| Directing | Kuki López Rodero | First Assistant Director |
| Directing | David Turchi | Second Assistant Director |
