The film was dedicated to actor Tony Beckley who played the villain in the original Terreur sur la ligne (1979).
Carol Kane, Charles Durning, and Cheryl Wilson are the only actors to reprise their roles from the previous film.
The schoolgirl outfit that Julia is wearing in the opening scene is based on the outfit that Janett Christman was wearing at the time of her death, which was a white blouse and a button-up skirt. She was babysitting two kids the night she was murdered, and her case served as an inspiration for "The Babysitter and the Man Upstairs" urban legend.
Jill Schoelen auditioned for the role of Julia wearing absolutely no makeup, with unkempt hair, and frumpy clothes. This is what won over Fred Walton, as he was initially skeptical of her and turned her down at first before giving her a chance to audition. A lot of the actresses that were auditioning were wearing makeup, pretty hairstyles, and fashionable clothes, and Walton was looking for an actress that would be believable as an introverted and shy teenage girl, and not someone who looked like a Hollywood starlet.
The scene where William nearly trips on the wet pavement after the club owner throws him out was unscripted. Gene Lythgow was originally just supposed to be shoved outside, but the actor nearly slipped on the wet concrete. Director Fred Walton was unaware of this until after the scene was finished, and initially thought he improvised it. The take is kept in the final cut.