* ActorInspiredElement: The script called for Dr Loomis to look shocked when Michael Myers's body disappears from the lawn. Creator/DonaldPleasance argued that he should have an "I knew this would happen" look. They shot it both ways and the latter was the one used.
* AFIS100YearsSeries:
** AFIS100Years100Thrills: #68
* TheBechdelTest: In the first scene with all the girls, they talk about schoolwork and their plans for the evening. Debra Hill apparently wrote the dialogue between the friends.
* CaliforniaDoubling: The movie was filmed in California, as opposed to Illinois. In several documentaries, Creator/JamieLeeCurtis and Creator/JohnCarpenter point out the various palm trees that can be spotted in the background.
* CreatorBacklash: Both Creator/JohnCarpenter and Debra Hill expressed displeasure at the DeathBySex trope's rise in horror after this movie. They said the reason the horny teenagers got killed was because they were too busy trying to do it that they failed to notice a killer approaching. Laurie only survives because she's on her own for most of the film.
* DawsonCasting: All of the teenagers are played by actors in their late twenties/early thirties. Even the least severe example--17/18-year old Laurie played by then-20 year old Creator/JamieLeeCurtis.
* MissingTrailerScene: An alternate version of Lynda on the phone to Laurie was shot for the trailer, because PJ Soles's blouse was open in the final film. So in the trailers and publicity stills, she is wearing a bathrobe instead.
* NoBudget: Only $320,000 was spent for this film, which is pretty amazing considering that it made ''$35,000,000''.
* {{Novelization}}: A very rare one now, that revealed a few plot points about Michael. It answers the PlotHole about how Myers knows how to drive - by watching Loomis carefully operate the car during their many sessions apparently. It also heavily suggests that Michael is possessed by the ghost of an ancient Celtic boy who murdered a girl he was in love with, making Michael an innocent victim.
* PlayingAgainstType: Creator/DonaldPleasence had been primarily playing villains (most famously [[Film/YouOnlyLiveTwice Ernst Stavro Blofeld]]) up until this point.
* RealLifeWritesThePlot: The original script had the murders take place over several days. Due to the low budget, filmmakers minimized the amount of set and costume changes and had the story happen only on one night. This also wrote the title, as they decided to place the plot on Halloween night.
* {{Recut}}: During the filming of the sequel, Creator/JohnCarpenter shot more scenes for the ABC broadcast of the film to help it pad out the allotted time. While largely just character exposition, one scene ([[spoiler:a visit to Michael's asylum room where the word "sister" is carved in the door]]) serves to help validate the twist of the second movie.
* RomanceOnTheSet: Nancy Loomis dated and eventually married Tommy Lee Wallace. They ended up divorced.
* SoMyKidsCanWatch: Creator/DonaldPleasence confessed to Creator/JohnCarpenter that the main reason why he took the part of Loomis was because his daughter Angela (who was a musician) had loved Carpenter's musical score for ''Film/AssaultOnPrecinct13''.
* StarMakingRole: For Creator/JamieLeeCurtis. She did get typecast as a FinalGirl for a few years before properly shaking that off and establishing herself as a star in her own right.
* StuntCasting: Creator/JohnCarpenter originally wasn't interested in the unknown Creator/JamieLeeCurtis as Laurie. But when he heard she was the daughter of ''{{Film/Psycho}}'''s Creator/JanetLeigh, he cast her in the hopes of drumming up publicity.
* WhatCouldHaveBeen:
** Creator/ChristopherLee turned down the role of Dr. Loomis and later said it was the biggest mistake he ever made in his career.
** Also, Creator/PeterCushing was the first choice to play Dr. Loomis, but [[Film/ANewHope since he'd recently appeared in ''another'' little independent film]], his asking price went higher than the studio was willing to pay.
** Also considered for Dr. Loomis were Cretor/PeterOToole, Creator/MelBrooks, Steven Hill, Creator/WalterMatthau, [[Series/MyMotherTheCar Jerry Van Dyke]], Lawrence Tierney, Creator/KirkDouglas, Creator/JohnBelushi, Lloyd Bridges, Abe Vigoda, Kris Kristofferson, Creator/SterlingHayden, [[Series/KungFu David Carradine]], Creator/DennisHopper, Charles Napier, Creator/YulBrynner and Edward Bunker
** Dennis Quaid was offered the role of Bob (Lynda's boyfriend) since he was dating P.J. Soles at the time, but had to turn it down due to work on another movie.
** There were two masks to choose from - the more familiar Captain Kirk mask, and a MonsterClown one (as a nod to Michael killing his sister while dressed as a clown). While they found the clown one scary too, the Captain Kirk one was ruled better because it was emotionless. Other masks considered include RichardNixon, Spock and Emmett Kelly.
** Originally, Dr. Loomis was supposed to have a phone conversation with his wife. Creator/DonaldPleasence didn't do it, saying he thought the character shouldn't have a family or a past.
** There was originally no music in the film at all. When one female critic complained the film wasn't scary, Creator/JohnCarpenter composed a score in three days.
** Anne Lockhart, daughter of ''Lassie'''s June Lockhart, was Carpenter's first choice for Laurie. But she had other commitments and couldn't do it.
* WorkingTitle: The initial storydraft was called ''The Babysitter Murders''.
* WriteWhatYouKnow: The characters are all named after people Creator/JohnCarpenter and Debra Hill knew. Haddonfield was where Debra Hill had grown up in New Jersey.
** The story is based on an experience Carpenter had in college touring a psychiatric hospital. Carpenter met a child who stared at him "with a look of evil, and it terrified me."
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