* CastTheRunnerUp: Creator/LisaLanglois auditioned for the role of Ann, but the role went to Tracey Bregman instead. She was cast as Amelia.
* DawsonCasting: 25-year-old Matt Craven as one of many 20-something teens.
* ExecutiveMeddling:
** The DVD was butchered when it first came out: a bland computer graphic of a girl with a birthday cake (and a castle being shown outside the window) was used because the studio felt no one cared about 80s slasher films and wanted to trick people into thinking it was a new Direct-To-DVD film instead. They also haphazardly used a different print which had a completely different soundtrack, one that was used as a placeholder while the real one was being finished. They later fixed these things when the film was re-issued by Anchor Bay several years later. Creator/MillCreekEntertainment's Blu-ray release (in a double feature with ''Film/WhenAStrangerCalls'') leaves the original film intact as well.
** Some of the kills in the film were trimmed down to avoid an X-rating. Most notably, the motorcycle and weight-lift kills.
* FollowTheLeader: Although it seems to have been directly influenced by the success of ''Film/FridayThe13th1980'' and ''Film/PromNight'', pre-production had started before those films had been released, which more than hints that the huge success of ''Film/Halloween1978'' was perhaps more of an influence (although the Grand Guignol elements of ''Friday the 13th'' may also have contributed).
* HostilityOnTheSet: Creator/GlennFord was less-than-thrilled to be in a slasher film and was reportedly drinking heavily during production. He and assistant director Charles Braive were involved in a dispute on set in which the actor allegedly hit the AD. In an interview with ''The Terror Trap'', producer John Dunning said:
-->He hit our AD, who had called a lunch break in the middle of one of Glenn's scenes. I had to stop the police from arresting him. It was a mess. Glenn wouldn't come out of his dressing room until the first AD apologized, who said he would never apologize to Glenn. But I told him that this might be the end of his career as an AD if he didn't. So, he went and said he was sorry...and Glenn said he was sorry. They kissed and made up. As far as I know, Glenn never hit anybody else.
* StarDerailingRole: This film's failure arguably killed Melissa Sue Anderson's career. Fresh off the success of ''Series/LittleHouseOnThePrairie'', her starring in a B-grade slasher must not have looked too good on a resume for her career ever since has been filled with nothing but D-list projects at best. Despite this, it later became a CultClassic among slasher aficionados.
* ThrowItIn: [[spoiler:The director wasn't happy with the original scripted ending where Virginia simply turns out to be the killer and the twist ending was come up with in the spot]].
* WhatCouldHaveBeen:
** According to an interview with Creator/LisaLanglois, her character Amelia was originally killed off. In the first cut of the film, her character got an axe to her head. Langlois was told by David Douglas (a cameraman on the set) that the film would have been rated X if they kept that scene intact. [[spoiler:So instead, the producers decided to make her look like the sole survivor in the final release.]]
** [[http://www.terrortrap.com/interviews/johndunning/ In a 2011]] interview with the website ''The Terror Trap'', producer John Dunning revealed he had discovered a box of some kill scene cuts that were made for the Canadian film board. His plan was to put the trims together, compare it to the U.S. release to see what’s missing, and try and get Columbia to put the missing cuts back in. Unfortunately, nothing seemingly came of it and [[DiedDuringProduction Dunning would pass away that same year]].
** The specialized genre website ''Retro Slashers'' has a copy of the script purporting to be a third draft from April 1980, where the major difference is that Virginia is actually the killer, possessed by the spirit of her deceased mother. Although this ending logistically makes more sense than the ending that was filmed, the filmmakers thought that what was originally scripted was not climactic enough. Still, the majority of the film does point to this original ending, which indicates the switch came well into production. This version of the script also features a good number of scenes that were either never shot or rewritten, including some that show more clearly Alfred's love for Virginia and Virginia's difficult relationship with her father.
* WritingByTheSeatOfYourPants: Among other things, the TwistEnding was written into the film after production began. They had already filmed [[spoiler:Ann's death scene by the time they informed her actress that she was now playing the killer]].
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