 | David Duchovny als Agent Fox Mulder |
 | Gillian Anderson als Agent Dana Scully |
 | Mitch Pileggi als Assistant Director Walter Skinner |
 | William B. Davis als The Cigarette-Smoking Man |
 | John Neville als The Well-Manicured Man |
 | Martin Landau als Kurtzweil |
 | Jeffrey DeMunn als Bronschweig |
 | Tom Braidwood als Frohike |
 | Blythe Danner als Cassidy |
 | Terry O'Quinn als Michaud |
 | Dean Haglund als Langly |
 | Bruce Harwood als Byers |
 | Armin Mueller-Stahl als Strughold |
 | Lucas Black als Stevie |
 | Christopher Fennell als 2nd Boy |
 | Cody Newton als 3rd Boy |
| Blake Stokes als 4th Boy |
 | Don S. Williams als Group Elder |
 | George Murdock als 2nd Elder |
 | Michael Shamus Wiles als Black-Haired Man |
 | Darrell Davis als Primitive #1 |
| Carrick O'Quinn als Primitive #2 |
 | Tom Woodruff Jr. als Creature #1 |
| Greg Ballora als Creature #2 |
 | Ted King als FBI Agent on Roof |
| Luis Beckford als FBI Agent |
 | Steve Rankin als Field Agent |
 | Gary Grubbs als Fire Captain Cooles |
 | Steven M. Gagnon als Last Agent Out |
 | Larry Joshua als DC Cop |
| Glendon Rich als DC Cop #2 |
 | Gunther Jenson als Security Guard |
 | Scott Alan Smith als Technician |
 | Ian Ruskin als Well-Manicured Man's Valet |
| Paul Welterlen als Control Room Operator |
| Joel Traywick als Young Naval Guard |
| Milton Johns als British Valet |
 | Michael Krawic als 2nd Paramedic |
 | Larry Rippenkroeger als Towncar Driver |
 | Josh McLaglen als Buzz Mihoe |
 | Randy Hall als Windbreakered Agent |
| T.C. Badalato als Fireman |
| Amine Zary als Tunisian |
| David Paris als Pilot |
 | Vanessa Morley als Young Samantha Mulder (archive footage) |
 | Jason Beghe als FBI Man at Bomb Site (uncredited) |
 | Glenne Headly als Barmaid |
| Chris Carter | Screenplay |
| Jackie Carr | Set Decoration |
| Chris Carter | Story |
| Lata Ryan | Executive Producer |
| Mark Snow | Original Music Composer |
| Gregory Bolton | Art Direction |
| Meg Liberman | Casting |
| Daniel Sackheim | Producer |
| Stephen Mark | Editor |
| Rob Bowman | Director |
| Ward Russell | Director of Photography |
| Chris Carter | Producer |
| Hugo Santiago | Art Direction |
| Frank Spotnitz | Story |
| Christopher Nowak | Production Design |
| Marlene Stewart | Costume Design |
| Mary Astadourian | Associate Producer |
| Phil Bowen | Aerial Camera Technician |
| Matthew A. Del Ruth | Camera Loader |
| Steve Duncan | Transportation Coordinator |
| Peter Koczera | Digital Effects Supervisor |
| David Womark | Unit Production Manager |
| Josh McLaglen | First Assistant Director |
| Doris Donnenberg | Production Supervisor |
| Jeff Charbonneau | Music Editor |
| Stan Blackwell | Special Effects Supervisor |
| Dins W. W. Danielsen | Assistant Art Director |
| Fanée Aaron | Set Designer |
| Carl Boles | Gaffer |
| Gino Crognale | Key Makeup Artist |
| Nancy Collini | Set Costumer |
| Alec Gillis | Makeup Effects |
| Alex L. Worman | Unit Publicist |
| Dennis McNeill | Color Timer |
| Margaret Adachi | First Assistant Editor |
| Michael J. Burmeister | Location Manager |
| Fred Simon | Visual Effects |
| Jennifer Jaafar | Art Department Assistant |
| Merrick Morton | Still Photographer |
| Jenna Abrahamson-Minardi | Lighting Technician |
| Mark Steinbeck | Boom Operator |
| Blake R. Cornett | Assistant Sound Editor |
| Paul Urmson | Sound Designer |
| Paul Apted | Sound Effects Editor |
| Derek Hurd | Craft Service |
| Samuel H. Adams | Propmaker |
| Howard Bachrach | Transportation Captain |
| Patti McNulty | Art Department Coordinator |
| Mark La Bonge | Camera Operator |
| Carrie L.A. | Location Scout |
| Lloyd Ahern II | Additional Photography |
| Kerry Mendenhall | Key Hair Stylist |
| Mike Carrillo | Property Master |
| Brian Bennett | Stunts |
| Stevie Lazo | Production Accountant |
| Michael Gates | Painter |
| Perry Petrzilka | Production Manager |
| David Was | Music Supervisor |
| John A. Larsen | Supervising Sound Editor |
| Brad Edmiston | First Assistant Camera |
| Paul J. Lombardi | Special Effects Coordinator |
| Mark Ballentine | Best Boy Electric |
| Kenneth Au | Digital Compositors |
| Marc Fisichella | Supervising Art Director |
| Lance Anderson | Prosthetic Makeup Artist |
| Craig Heath | Sound Recordist |
| Dina Farnell | Production Coordinator |
| Jonathan Sacks | Orchestrator |
| Mark Kenna | Dolby Consultant |
| Bill Iiams | Construction Coordinator |
| Don Poole | Driver |
| Tim A. Davison | Stunt Coordinator |
| Maxwell R. Johnson II | Transportation Co-Captain |
| Daphne Dentz | Visual Effects Coordinator |
| Tim Donelan | Leadman |
| Ronnie Lombard | Set Dressing Artist |
| Mike Amorelli | Rigging Gaffer |
| Pasquale Attanasio | Rigging Grip |
| Matthew Ferro | Visual Effects Producer |
| Fred Fein | Stand In |
| Mark Suveg | Video Assist Operator |
| Tricia Ronten | Script Supervisor |
| Harold Groshon | Electrician |
| R.J. Kizer | ADR Supervisor |
| James N. Delaplane | Standby Painter |
| Jason Bell | Grip |
| Todd J. Adelman | Set Medic |
| Geoffrey Patterson | Sound Mixer |
| James Sweet | Key Grip |
| John Casey | Costume Supervisor |
| Damian 'Rocky' Polito | Carpenter |
| Robert Mendoza | Post Production Assistant |
| Rachel Flackett | Set Production Assistant |
| Pamela Choules | Visual Effects Editor |
| Susan Dawes | Dialogue Editor |
| Mat Beck | Visual Effects Supervisor |
| Rodger Pardee | Sound |
| Jim Martin | Production Illustrator |
| Erik Henry | Additional Visual Effects |
| Jeff Cahn | Assistant Editor |
| Chad C. Barrow | Best Boy Grip |
| Merritt Gold | Focus Puller |
| Julie Ann Moyeda | Payroll Accountant |
| John Nein | Production Secretary |
| Renato De Cotiis | Additional Third Assistant Director |
| Tim Flattery | Concept Artist |
| Michael Cassidy | Second Assistant Camera |
| Susan A. Burig | Graphic Designer |
| Jamie Sewell | Clapper Loader |
| Robb Bihun | Storyboard Artist |
| Scott D. Mattson | Special Effects Assistant |
| Phil Booth | Third Assistant Director |
| Howard Fannon | Assistant Property Master |
| David Betancourt | Foley Mixer |
| Christopher Leone | VFX Artist |
| Jim Cashman | Visual Effects Production Assistant |
| Heather Burton | Stunt Double |
| Max E. Brehme | Swing |
| Ramsey McDaniel | Title Designer |
| Miyuki Takahashi | 2D Artist |
| Tom Gleason | Assistant Camera |
| Stephen Sobisky | Project Manager |
| Mark Snow | Conductor |
| Jennifer S. Deayton | Assistant Production Coordinator |
| Helen Monaghan | Key Costumer |
| Diane Linn | ADR Recordist |
| Jan Beran | Special Effects Technician |
| Patrick Rush | Additional Casting |
| Timothy Falconer | Assistant Location Manager |
| Greg Strause | Digital Supervisor |
| Kelly Richards Ralston | First Assistant Accountant |
| Anna Bradley | Key Set Production Assistant |
| Dawn Fintor | Foley Artist |
| Michael Mills | Makeup Supervisor |
| Jeff Hamon | ADR Mixer |
| Edwin Rivera | 2D Supervisor |
| Travis Baumann | Compositing Artist |
| James Bolt | Additional Sound Re-Recording Mixer |
| Carrie Cashman | Foley Recordist |
| Ricky Cuevas | Assistant Accountant |
| Jill Hall | Set Dressing Buyer |
| Gary Burritt | Negative Cutter |
| David Paris | Aerial Coordinator |
| Shaun M. McGovern | Second Assistant Accountant |
| Rich Sickler | Second Second Assistant Director |
| Rick Kangrga | Dolly Grip |
| Janet Tebrooke | Wardrobe Supervisor |
| Jerry Solomon | Chief Lighting Technician |
| David M. Wermus | Location Assistant |
| Erik Liles | Senior Animator |
| Angela Terry | Casting Assistant |
| Linda Gregory | Accountant |
| Dave Casella | Production Assistant |
| William O. Heaton | Technical Advisor |
| William H. Burton Sr. | Second Unit Director |
| Nancy Thurston | Stunts |
| Lisa Dempsey | Stunts |
| Jon H. Epstein | Stunt Double |
| Frank Spotnitz | Co-Producer |
| Troy Robinson | Stunts |
| Troy Brown | Stunts |
| Bob Brown | Stunts |
| Gregory J. Barnett | Stunts |
| Steve M. Davison | Stunts |
| John C. Meier | Stunts |
| Billy D. Lucas | Stunts |
| Michael Runyard | Stunts |
| Kendel McMurray | Stunts |
| Jimmy N. Roberts | Stunts |
| William H. Burton Jr. | Stunts |
| Chris Blackwood | Stunts |
| Hal Burton | Stunts |
| Dale Gibson | Stunts |
| Dane Farwell | Stunts |
| Steve Holladay | Stunts |
| James M. Halty | Stunts |
| Tommy J. Huff | Stunts |
| Claudette James | Stunt Double |
| Shawn Kautz | Stunts |
| Dennis Madalone | Stunts |
| Khristian Lupo | Stunts |
| Erik Rondell | Stunts |
| Jimmy Romano | Stunts |
| James Ryan | Stunts |
| Craig Shugart | Stunts |
| David Schultz | Stunts |
| Thomas DuPont | Stunts |
| Roger Wells | Stunts |
| Scott Hubbell | Stunts |
| Robert Powell | Stunts |
| Colin Nicolson | Sound Mixer |
