 The episode is one of the few in the series that has no paranormal elements to it . Carter said of the episode 's conception , " My first chance to work with David Nutter in a long time , and I wanted to give him something he could sink his teeth into . It 's a little bit different for us . It doesn 't really have a paranormal aspect , except for Scully 's perceptions of her deepest fears . I felt that I had to figure out what she is most afraid of , and she is most afraid of those things that most of us are afraid of . The idea of dying at the hands of someone — creature or not — and she is helpless to do anything about it . I thought it was a very good way to explore Scully 's character . " The scene where Dana Scully imagines Pfaster appearing as a devil was influenced by real @-@ life accounts , as described by Carter : " There are reports of people who had been under the spell of Jeffrey <unk> , who actually claimed that he shape @-@ shifted during those hours when they were held hostage ; that his image actually changed . " Nutter said " In many ways , Chris wanted to sell the idea that , as established in Mulder 's closing dialogue in the show , not all terror comes from the paranormal . It could come from the person next door . " 
