 | Matthew Lillard als Col. Steven Isaac |
 | Paul Reubens als The Alien |
 | Kelly Hu als Dr. Annabelle Fermi |
 | Jack Hallett als Dr. Duxler |
 | Ravi Kapoor als Dr. Marc Allen |
 | Jane Lynch als Irene Maloof |
 | Bruce McGill als Gen. Keller |
 | Brandon Molale als Armed Soldier |
 | Mona Sishodia als Scientest 3 |
 | Kelvin Yu als Private Simms |
| Dean Parisot | Director |
| Mike Armstrong | Writer |
| Mike Armstrong | Executive Producer |
| Jane Bartelme | Producer |
| David Latt | Executive Producer |
| Dean Parisot | Executive Producer |
| Chad Savage | Co-Producer |
| John Adair | Original Music Composer |
| Steve Hampton | Original Music Composer |
| Robert K. Lambert | Editor |
| Doug Kraner | Production Design |
| Andy Clement | Special Effects Key Makeup Artist |
| Kimberly Felix | Makeup Department Head |
| Carol A. O'Connell | Hair Department Head |
| Todd Sharp | Executive In Charge Of Production |
| Lynne Martin | Second Second Assistant Director |
| Brian Feola | Construction Foreman |
| Mike Medina | Construction Foreman |
| Joe Monaco | On Set Dresser |
| Joe Monaco | Set Dresser |
| Michael Ruby | Sign Painter |
| David Hadder | Boom Operator |
| Jack Levy | Supervising Sound Editor |
| Doug Madick | Foley Artist |
| Richard Partlow | Foley Artist |
| David J. Barker | Special Effects Technician |
| Michael Del Genio | Special Effects Technician |
| Ronald Zarro | Special Effects Supervisor |
| Doug Drexler | Visual Effects Supervisor |
| Michael Gibson | Visual Effects Producer |
| Nina Harlan | Compositor |
| Jack Marshall | Visual Effects Coordinator |
| Heather McAuliff | Digital Compositor |
| Alex Daniels | Stunt Coordinator |
| Ian Eyre | Stunt Double |
| Michael Li | Stunts |
| Norb Phillips | Stunts |
| Buddy Sosthand | Stunts |
| Henry Cline | Camera Operator |
| Frank Dorowsky | Rigging Gaffer |
| Scott C. Keys | Rigging Grip |
| Ronald R. Koch Jr. | Electrician |
| Jeff Murrell | Chief Lighting Technician |
| Steve Reinhardt | Assistant Chief Lighting Technician |
| Katja Blichfeld | Casting Coordinator |
| Geralyn Flood | Casting Associate |
| Jamelle Flowers | Set Costumer |
| Lara Khachooni | Assistant Editor |
| Brad Hamilton | Music Editor |
| Brad Hamilton | Music Producer |
| Andy Paley | Original Music Composer |
| Jillinda Palmer | Music Editor |
| Mary Parker | Music Editor |
| Kerry Lyn McKissick | Script Supervisor |
| Joel Larson | Driver |
| Jonathan A. Rosenfeld | Transportation Coordinator |
| Jeff Verdick | Transportation Captain |
| Jenny Fumarolo | Production Coordinator |
| Tucker Maloney | Production Assistant |
| Sarah Quale | Assistant Production Coordinator |
