In one of several scenes removed from the theatrical version of the movie, Principal Hammond takes his wife to visit Dr. Fairchild after a visit to Robin's resting place at the cemetery. As Vivian is seated in the office and the men talk privately in the hallway, it is revealed that Robin and Alex are twins.
According to director Paul Lynch in the documentary "Going to Pieces: The Rise and Fall of the Slasher Film", he was having difficulty securing financing until Jamie Lee Curtis signed on. Once the film was shot, Paramount expressed interest in distributing the movie. However, they only wanted to open it in 300 theaters whereas Avco Embassy Pictures offered to release it in 1200 theaters. Avco Embassy released Prom Night as a result. That same year, Paramount released another independent slasher film, Friday the 13th (1980).
Hamilton High custodian Mr. Sykes, albeit drunk on the evening of the prom, knew that a killer was loose because he was secluded in the same storage room that Wendy ran into when she was being pursued. You can see the camera pan left to his silhouette shortly after she enters the space to hide.
According to Paul Zaza, the prom scene was shot with actual disco hits that the production company later realized they couldn't afford the rights to. This gave Zaza a week and a half to create similar, origonal disco songs for the film that were close, but not so close they could be sued.
There were deleted scenes of Leslie Nielson talking morosely about his daughter's death to a doctor, and also scenes of him chopping wood, which were meant to point him out as a suspect. There were also deleted scenes with a psychiatrist telling Leslie Nielson that his wife has serious problems, not just depression over his daughter's death, and another scene with her looking at a picture of Robin on the wall surrounded by flowers, which were meant to make Mrs. Hammond look like a suspect. There was also a scene with Leslie Nielson talking to a psychiatrist about Robin's death and it's impact on Kim, how she gets depressed from time to time; and how Robin and Alex were twins, but Alex doesn't remember the death at all.
When the raspy voiced caller in the room dials the residences of Jude, Kelly, Nick and Wendy respectively, the area code on the rotary phone begins with 614. Although the movie was shot in Toronto, Canada this area code is for Central Ohio.
As gym teacher Henri-Anne Benton is giving decorating instructions to Biology teacher Monty Weller in the gym and Kim runs in, she apologizes for being late and Mr. Weller calls her "The literary Ms. Hammond". This is related to one of several scenes deleted from the theatrical version (but returned to the network TV version) of the movie when the girls are dissecting frogs and are caught sneaking Jude's note about her last-minute prom date, Slick. Mr. Weller wrongfully accuses Kim of possessing the note and forces her to read it aloud to the class.
When Ms. Benson says to Mr. Weller at the prom "I believe this is OUR dance, Monty", he was in the company of Adele Cooper, the substitute secretary for Principal Hammond. She is a character whose scenes were removed from the theatrical version (but returned to the TV version) of the movie.
"Prom Night" would not be the only movie actresses Jamie Lee Curtis and Anne-Marie Martin would star in together: Jamie would reprise her role as Laurie Strode for Halloween II (1981) and Anne-Marie would play Darcy, Nurse Karen's friend in the film that is promised a ride home from the party at Stevie Mackie's house. The latter was uncredited for her brief appearance.
According to Horror at Hamilton High a documentary about the making of Prom Night Eve Plumb was all set to play Kim. At the last minute Jamie Lee Curtis' people expressed an interest, and Eve was replaced.
This was much more artfully made then Friday the 13th, (which came out the same year and was a similar holiday themed slasher movie riding on the coattails of Halloween with a revenge story at its core). But for some reason Friday the 13th was a phenomenon, and while this was a hit, and it got better reviews, it did not have the same impact.
The main plot about children committing a horrible sin and all swearing to secrecy only to be stalked years later by a vengeful killer would later used as the plot for the 1997 thriller I Know What You Did Last Summer.
Director Paul Lynch developed Prom Night after a meeting with producer Irwin Yablans. Lynch had wanted to work on a horror film, and, in response to Yablan's suggestion that he utilize a holiday as a basis for the film, Lynch decided on building the premise around the event of the high school prom.
Prom Night was filmed over twenty-four days in Toronto, Ontario, Canada from August 7 to September 13, 1979. The Don Mills Collegiate Institute served as the main school location, while the Langstaff Jail Farm in Richmond Hill was used for the abandoned building featured prominently in the beginning of the film.
As with Carrie this is a revenge movie focusing on the prom; and as with Carrie there is a prank at the beginning which ends up having disastrous consequences. Also like Carrie in that the prom queen is supposed to be victimized by a staged prank; and as with Carrie you have a fake prom king and queen standing in for the real king and queen. But whereas in Carrie the prom queen ends up being victimized at the prom (she is drenched in pig's blood), in Prom Night the prom king gets victimized (he is decapitated).
The trivia items below may give away important plot points.
David Mucci, who played troublemaker Lou, had a serious medical condition. He was forced to be immobilized underneath the stage for the scene in which Lou is decapitated. He was terrified that something would happen while he was trapped there so director Paul Lynch held his hand for the duration of the scene to assure him everything would be all right.