Six years after the events of The X-Files series finale, former FBI agent Doctor Dana Scully is now a staff physician at Our Lady of Sorrows, a Catholic hospital, and treating a boy named Christian who has Sandhoff disease, a terminal brain condition. FBI agent Drummy arrives to ask Scully’s help in locating Fox Mulder, the fugitive former head of the X-Files division, and says they will call off its manhunt for him if he will help investigate the disappearances of several women, including young FBI agent Monica Banan. Mulder and Scully are called back to duty by the FBI when a former priest claims to be receiving psychic visions pertaining to a kidnapped agent.
Unfortunately the movie The X Files: I Want to Believe is not yet available on HBO Max.
| Writing | Frank Spotnitz | Screenplay |
| Directing | Chris Carter | Director |
| Writing | Chris Carter | Screenplay |
| Production | Mindy Marin | Casting |
| Costume & Make-Up | Victoria Down | Makeup Department Head |
| Crew | E. J. Foerster | Second Unit |
| Art | David Hadaway | Set Designer |
| Costume & Make-Up | Leonardo Lara | Set Dressing Artist |
| Crew | Andrew Edwards | Compositors |
| Visual Effects | Graham Houston | CG Painter |
| Crew | Brian Sales | Compositors |
| Visual Effects | Trent Smith | Visual Effects Producer |
| Crew | Jennifer Mylrea | Stunts |
| Art | Tony Wohlgemuth | Art Direction |
| Crew | Christopher Mark Pinhey | Makeup Effects |
| Art | Cheryl Marion | Assistant Art Director |
| Crew | David Alexander | CG Supervisor |
| Crew | Jason Dunn | Compositors |
| Crew | Guy Bews | Stunts |
| Crew | Dave Lane | Stunts |
| Crew | Jeff Sanca | Stunts |
| Crew | Chris Webb | Stunts |
| Lighting | Ryan Bailey | Gaffer |
| Camera | Bill Roe | Director of Photography |
| Sound | Warren Hendriks | Sound Effects Editor |
| Sound | Erin Michael Rettig | Sound Engineer |
| Crew | Charles Collyer | Compositors |
| Visual Effects | Rod Park | Visual Effects Producer |
| Visual Effects | Andrea Shear | CG Painter |
| Crew | Christina Spring | Compositors |
| Crew | Donald Tse | Compositors |
| Visual Effects | Dmitry Vinnik | CG Painter |
| Crew | Duane Dickinson | Stunts |
| Production | Chris Carter | Producer |
| Art | Mark S. Freeborn | Production Design |
| Costume & Make-Up | Jared Brown | Set Dressing Artist |
| Art | Mike Rennison | Construction Coordinator |
| Sound | David Betancourt | Foley |
| Sound | Randall Guth | First Assistant Sound Editor |
| Camera | Mitch Bax | Camera Intern |
| Production | Heike Brandstatter | Casting |
| Costume & Make-Up | Lisa Tomczeszyn | Costume Design |
| Sound | Charleen Richards-Steeves | ADR & Dubbing |
| Visual Effects | Thomas F. Ford IV | Visual Effects Producer |
| Visual Effects | Andrew Lema | CG Painter |
| Crew | Patrick Thompson | Compositors |
| Crew | Todd Scott | Stunts |
| Crew | Natasha Vasiluk | Stunts |
| Crew | Marshall Virtue | Stunts |
| Editing | Richard A. Harris | Editor |
| Production | Coreen Mayrs | Casting |
| Sound | Paul Massey | Sound Re-Recording Mixer |
| Sound | Alicia Stevenson | Foley |
| Crew | David Gauthier | Special Effects Coordinator |
| Visual Effects | Glenn Curry | CG Painter |
| Crew | Richard Martin | Compositors |
| Crew | Pierre Raymond | Executive Visual Effects Producer |
| Production | Dan Rucinski | Production Supervisor |
| Production | Anne Tremblay | Administration |
| Crew | Mike Dobbin | Stunts |
| Production | Frank Spotnitz | Producer |
| Crew | David McKimmie | Post-Production Manager |
| Art | Sabine Schoppel | Art Department Coordinator |
| Sound | David Giammarco | Sound Re-Recording Mixer |
| Visual Effects | Anouk Deveault-Moreau | Visual Effects Supervisor |
| Crew | Marty Taylor | Compositors |
| Crew | Dave Williams | Compositors |
| Costume & Make-Up | Sandy Monesmith | Hairstylist |
| Crew | Ryan Epp | Compositors |
| Visual Effects | Jack Noriaki Matsumoto | CG Painter |
| Crew | Wayne A. Shepherd | Compositors |
| Crew | Mike Spring | Compositors |
| Crew | Dean Hart | Stunts |
| Art | Paul Rinaldi | Construction Foreman |
| Crew | Rodrigo Armendariz | Compositors |
| Visual Effects | Junji Hirano | CG Painter |
| Visual Effects | Daniel Leduc | Visual Effects Producer |
| Crew | Tony Morelli | Stunts Coordinator |
| Costume & Make-Up | Mark Prior | Set Dressing Artist |
| Writing | Jenny Seinen | Storyboard |
| Sound | David Grimaldi | Sound Effects Editor |
| Crew | Mark Goldberg | Compositors |
| Crew | Steve J. McLeod | Compositors |
| Sound | Mark Snow | Original Music Composer |
| Costume & Make-Up | Geoff Coulter | Set Dressing Artist |
| Sound | David Lucarelli | ADR & Dubbing |
| Crew | Michel Barrière | Compositors |
| Visual Effects | Mat Beck | Visual Effects Supervisor |
| Crew | Matthias Lowry | Compositors |
| Visual Effects | Randal Shore | Visual Effects Producer |
| Crew | Melissa R. Stubbs | Stunts |
| Costume & Make-Up | Gitte Axen | Makeup Artist |
| Visual Effects | Steve Au | CG Painter |
| Crew | Don Greenberg | Compositors |
| Crew | Corbin Fox | Stunts |
| Crew | Julio Pallares | Makeup Effects |
| Production | Wayne Bennett | Production Manager |
| Visual Effects | Brenda Ilic | Visual Effects Producer |
| Visual Effects | Eugene Paluso | CG Painter |
| Visual Effects | Ian Wilson | CG Painter |
| Crew | Kimberly Chiang | Stunts |
| Crew | Bill Edwards | Stunts |
| Camera | Matt Almas | Grip |
| Art | Shirley Inget | Set Decoration |
| Crew | Maureen Terezakis | Makeup Effects |
| Production | Simon Abbott | Production Manager |
| Crew | Paul Rabwin | Post Production Supervisor |
| Sound | Chuck Michael | Sound Designer |
| Visual Effects | Joni Jacobson | Visual Effects Producer |
| Crew | Vinay Mehta | Compositors |
| Visual Effects | Tena Montoya | Visual Effects Producer |
| Visual Effects | John C. Wash | Visual Effects Supervisor |
| Crew | George Collins | Video Assist Operator |
| Crew | Bill Terezakis | Makeup Effects |
| Costume & Make-Up | Raul Casillas | Set Dressing Artist |
| Costume & Make-Up | Scott Holburn | Set Dressing Artist |
| Sound | Martin Lacroix | Boom Operator |
| Crew | William Unrau | Cableman |
| Crew | Brian Petras | Compositors |
| Crew | Chris Atkinson | Stunts |
| Production | Brent O'Connor | Unit Production Manager |
| Crew | Linda Drake | Visual Effects Editor |
| Crew | James Bamford | Stunts |
| Crew | Mike Mitchell | Stunt Coordinator |
| Production | Brent O'Connor | Executive Producer |
| Directing | Portia Tickell | Script Supervisor |
| Sound | Matthew Harrison | Foley Editor |
| Art | Eric Partridge | Assistant Property Master |
| Sound | Eric A. Larsen | Assistant Sound Editor |
| Sound | Dennis Rogers | Sound Recordist |
| Visual Effects | Bryce Brecheisen | Visual Effects Coordinator |
| Camera | John S. Bartley | Second Unit Director of Photography |
| Sound | Tim Gomillion | Sound Recordist |
| Sound | Galen Goodpaster | Assistant Sound Editor |
| Art | Wayne McLaughlin | Property Master |
| Sound | Michael T. Williamson | Sound Mixer |
| Sound | Mildred Iatrou | ADR Editor |
| Sound | Smokey Cloud | Assistant Sound Editor |
| Camera | Cory Budney | First Assistant Camera |
| Art | Brad McMurray | Set Decorating Coordinator |
| Visual Effects | Shane Strickman | Visual Effects Coordinator |
| Sound | Scott Curtis | Foley Editor |
| Art | Marta McLaughlin | Assistant Property Master |
| Sound | Gloria D'Alessandro | Dialogue Editor |
| Production | Mark Sweatman | Production Assistant |
| Crew | Charles Andre | Stunts |
