In the screenplay stage and all the way through to production The Dark's antagonist was an abused, autistic child who had been locked in an attic for his entire life. His house was to burn down, allowing to him to escape and take his vengeance upon the unfamiliar outside world. Toward the end of the shoot, the producers decided they wanted to cash in on the success of Alien (1979), and demanded re-shoots to change the killer into a extra-terrestrial.
The television station is KFVI. The last part "FVI" refers to this film's production company, Film Ventures International. When Shelley is by the movie theater at the beginning of the film, two posters can be seen for Beyond the Door (1974) (aka "Beyond the Door") and The Night Child (1975) (aka "The Night Child"). These Italian horror films were distributed by Film Ventures International.