"The X-Files: I Want to Believe" is a stand-alone story in the tradition of some of the show's most acclaimed and beloved episodes, and takes the complicated relationship between Fox Mulder (Duchovny) and Dana Scully (Anderson) in unexpected directions. Mulder continues his unshakable quest for the truth, and Scully, the passionate, ferociously intelligent physician, remains inextricably tied to Mulder's pursuits.