Second appearance in the series of The Lone Gunmen. They were originally only intended to appear in the season 1 episode E.B.E. (1994), but they proved so popular on internet forums that they were revived for this episode.
The doorbell buzzing that drives Ed mad is actually spelling out KILL in Morse code.
When the cop is talking to Mulder about the cities that might be accustomed to murders, he says that celebrities don't drive around with guns to their heads in his city. This is a reference to O.J. Simpson.
The images Edward Funsch sees on the TVs in the department store are: Charles Manson; the attack on Reginald Denny; the beating by police of Rodney King; the conflagration that resulted from the FBI's and ATF's storming of the Davidians compound in Waco, Texas; the LA riots that followed the acquittal of King's attackers; and the O.J. Simpson police chase.
Although he had played the monster in the previous episode, The Host (1994), this marks the first time that Darin Morgan contributed to the series in a writing capacity.