Though the filmmakers did their best to make Halloween II seem like a direct continuation from Halloween, the three-year gap in filming meant there were certain things they couldn’t control, as well as continuity errors that amounted from it.
- Seven gun shots can be heard at the beginning of the film, despite Dr. Loomis’ gun being a six-shooter. Additionally, he repeatedly says he shot Michael six times throughout the film’s duration.
- There are several inconsistencies with Laurie’s appearance between the first film and the sequel. The first film had her wearing denim bell-bottoms, but the sequel has her in tight blue jeans; Her silver ring moves from her left hand in the original to her right hand in the sequel; and her injury goes from being on her upper arm to being higher on her shoulder.
- The landscaping for both the Doyle and Wallace house has changed considerably between this film and the first film.
- In the original film, Michael is shot off of the balcony, and it’s in the bark year. The sequel changes it to have Michael be shot off the front balcony.
- The lights on the Doyle’s front door change depending on whether it’s footage taken from the original film’s archival footage, or newly filmed footage for the sequel.
- The pumpkin on the Wallace porch is noticeably different in this film than it was in the original.
- The film takes place in 1978, but the ambulance has rectangular headlights, which were not introduced on full-size Ford vans until the 1980 model year.
As a result of the film having a few different edits and John Carpenter becoming involved, several plot points and goofs arrive from the removal and shuffling of scenes.
- Michael watches Jimmy and Karen have a conversation from the baby ward before going down the stairs. Later on, he watches Karen from the same baby ward before going into hospital room that he had already exited earlier.
- The television version presents these scenes in a different order, negating this continuity error.
- Later on, when Michael makes an attempt to stab Laurie’s bed, he leaves with the door open. Jill shows up, and the door is closed.
- The television version extends Michael leaving the room to show him pulling the door shut behind him, but this is missing from the theatrical cut.
- The television version features more footage of Mr. Garrett in the basement, where he talks about the phone lines being cut after Mrs. Alves has already mentioned the phones not working. We see Jill on the phone later on.
- When Michael sees Alice from outside her home, she is holding the phone in her left hand. In the next shot, which was filmed during the reshoots, she is holding the phone in her right hand.
Elsewhere, the film also contains the following goofs.
- While Jimmy tells Laurie that they’re taking her to the clinic and the news continues to refer to it as a clinic, the uniforms everyone wears and all the signs refer to it as Haddonfield Memorial Hospital.
- The ambulance transporting Laurie to the hospital can be seen behind Gary and his mother when they’re in the parking lot. The next shot shows that same ambulance pulling in to the parking lot.
- After Ben Tramer is hit by the patrol car, his body slumps onto the hood. When Dr. Loomis and Sheriff Brackett see him later, he is an upright position and remains there.
- The car that hits Ben Tramer changes from a Dodge Monaco to a Plymouth fury.
- The blanket covering Annie Bracket changes positions between shots when Sheriff Brackett examines her body.
- Furthermore, when he goes to close her eyes, you can see the actress Nancy Keys blink underneath Charles Cyphers’ hand.
- Deputy Hunt calls for back-up at “45 Lampkin Lane,” which is the address used for the Myers house in the films. However, the address on the house clearly reads 709.
- Karen’s belt is brown in her first scene, but white for the rest of the film.
- In the television version, Jill is seen talking on the phone after it’s already established they’re no longer working.
- Bud goes to clear condensation off the hot tub, but there is none there.
- Dr. Loomis shoots out the window in the Marshal’s car, but it’s intact in later scenes.
- The car horn continues to blare after Laurie pulls Jimmy’s head from the steering wheel.
- While on fire, Michael walks past the same stretcher twice.