X-Files: I Want to Believe is strictly for serious fans of Mulder and Scully on the small screen, the critics say. Gillian Anderson and David Duchovny's plunge back into the paranormal "gives devoted fans plenty of small moments to swoon over," Brian Lowry writes in Variety, "but the appeal should be limited beyond those fervent loyalists."
The stars bring some of the spooky old atmosphere back, Richard Corliss writes in Time, "but so much has changed that they seem the aliens." The film, Jan Stuart writes for the LA Times, "is not so much interested in setting up a dialectic between clashing belief systems as it is in delivering a socko FBI procedural. In both instances, it falls woefully short."