 | Cotter Smith als Sergeant Sam Taliaferro |
 | Mel Harris als Dr. Nora Haley |
 | Scott Curtis als Cameron Lansing |
 | Chuck McCann als Ben Majors |
 | Leigh McCloskey als Pete Groom |
 | Kim Lankford als Dory Lansing |
 | Gary Hudson als Bob Froelich |
 | Tab Hunter als Owen Lansing |
 | Dort Clark als Alan Wilson |
 | David Povall als Capt. Navarro |
 | Wilson Smith als Joe Crespy |
| Kerry Yo Nakagawa als Policeman |
| Raymond Patterson als Physician |
| Skip E. Lowe als Newscaster |
| Bonnie Bradigan als Newswoman |
 | Frank Pesce als Ed Wallace |
| Paul W. Zecevic als Reporter |
| Doc D. Charbonneau als Little Demon |
 | William Lustig als Ice Cream Eater (uncredited) |
| Armand Mastroianni | Director |
| Gary Brandner | Screenplay |
| Paul A. Edwards | Additional Photography |
| Luigi Cingolani | Producer |
| John S. Curran | Line Producer |
| George Zecevic | Executive Producer |
| Franc Caggiano | Associate Producer |
| Harry Manfredini | Original Music Composer |
| Russell Carpenter | Director of Photography |
| Frank De Palma | Editor |
| Ann Remsen Manners | Casting |
| Mike Bingham | Production Design |
| Sarah Burdick Stone | Set Decoration |
| Rose Librizzi | Makeup Artist |
| Rose Librizzi | Prosthetic Makeup Artist |
| Alex Rambaldi | Prosthetic Makeup Artist |
| Kelly Van Horn | Unit Production Manager |
| Ara Ashjian | Sound Recordist |
| Kenneth R. Burton | Sound Recordist |
| Gregory Cheever | Sound Recordist |
| Greg Landerer | Special Effects |
| Carlo Rambaldi | Creature Design |
| Ermando Biamonte | Visual Effects Supervisor |
| Spiro Razatos | Stunt Coordinator |
| Cheryl Wheeler Duncan | Stunts |
