 The scene where Mulder-as-Fletcher encounters his reflection and proceeds to dance is an homage to the 1933 Marx Brothers comedy film Duck Soup. Originally, during production meetings, the staff of The X-Files decided to create the scene by using digital technology, although this method would raise the budget significantly. Duchovny and McKean, however, volunteered to shoot the film the "old fashioned way" by choreographing their moves so that they would be in-synch. Duchovny and McKean each watched Duck Soup and then practiced for a week and a half in order to perfect the scene. When the scene was filmed, a metronome was present so that the two actors could keep time with each other. This was then erased from the mix during post-production. In addition, the set was actually two bedrooms, both mirror images of each other. The only part that featured any CGI was when Mulder blows on the mirror, producing fog. According to director Kim Manners, Duchovny and McKean filmed the shot that was used on the twelfth take.
