Continuity mistake: When Loomis thinks he sees Michael but it is actually a drunk Ben Tramer in a mask, he runs after Tramer and pulls his gun. Brackett sees this and runs out of his patrol car, slams the door, and stops Loomis before Loomis gets off a shot. A few seconds later though, the car door is now open in the background.
Revealing mistake: When Doctor Loomis touches the blood in the beginning, you can see a bit of material (it appears to be plastic) sticking to his fingers as he pulls them up from the grass. It appears as though it was somehow involved in the effect of him touching the blood. (Perhaps to keep it from soaking into the ground?).
Plot hole: In the first scene Alice hears on the radio that three teenagers had been murdered in Haddonfield just down the street from where they live. Yet a few scenes later, the sheriff finds out from his deputy that 3 bodies have been found. Wouldn't the police department know that before it made its way onto the radio news?Jeanne Elizabeth Perrotta
Continuity mistake: Near the film's climax, the marshall is shown walking down a hallway by a soda machine and reacts to Laurie's screaming. He then makes a turn around to go see what was up. Several seconds (and many screams) later, Michael crashes through the door and the marshall is still running down the hallway by the same soda machine.
Other mistake: When Bud goes to check on how hot the water is, he rubs condensation off the gauges, but there wasn't anything on them to begin with.
Continuity mistake: The balcony from which Michael Myers falls from in Halloween 2 is different than the original Halloween. You can clearly see a canopy over-hanging the balcony in the original, but in Halloween 2 the canopy is missing. It appears that Michael's body falls and lands in two completely different areas between the two movies.
Continuity mistake: When nurse Karen first enters the hospital and changes into her uniform, she's clearly shown putting on a dark belt (either black or brown). However, in her next scene with Mrs. Alves, as well as the scene where she's tricked into entering the hospital room to fool around with Bud, the belt is white.
Continuity mistake: In the scene where the boys ask Mr. Hunt about Ben Tramer, Mr. Hunt says that "it's just a little past 11." Following this up in the next scene Bud lures Karen into the room to kiss her and wish her Happy Halloween. During this scene, as Bud reaches up to kiss Karen, his watch is clearly visible and shows the time as 1:00.
Continuity mistake: After getting out of the car, Laurie is on the ground beside Jimmy's car outside the hospital when she sees the Marshall's car pull up. When Loomis tells the Marshall he ought to handcuff him to the wheel, if you look, Jimmy's car is still visible in the distance, but Laurie is not in that shot.
Continuity mistake: The flashing lights on the front of Bud and Jimmy's ambulance change places as they pull into the hospital driveway. They go from either the side of the hood to the front of the bumper.