Continuity mistake: Dr. Loomis seems to make the trip from Haddonfield to Smith's Grove (150 miles apart) in an impossibly short time.
Continuity mistake: When Tommy goes back to the bus depot, he finds a blood trail that was left by Jamie when she died the previous night. Tommy's there during the day or early morning and when Tommy finds the blood in the sink, he touches it and it's still wet. Blood dries in only 4 minutes so it couldn't have been left by Jamie.
Continuity mistake: Tommy goes to the bus station and a map of the towns of Illinois appears on the wall. Notice that Haddonfield and Smiths Grove (150 miles apart in the film) are located in between Pontiac and Dwight which are 18 miles apart in reality! That's how far apart the Amtrak stations are from each other according to the Amtrak timetable/schedule.
Continuity mistake: In the opening of the original Halloween, the backyard of the Myers house is level with the back door leading to the kitchen. In this movie, the kitchen door is accessed by steps showing that it is high off the ground, and also means that the house is on an embankment. If this is true, why does Kara walk on completely flat ground while going by the side of the house?
Continuity mistake: In the scene where Michael Myers impales the nurse's head on a spike in the darkened hallway, we first see Michael walking mysteriously out of the darkness & in plain sight of the nurse. Then the camera angle changes to Michael's POV and he doesn't see the nurse until he walks around the corner.
Plot hole: Michael kills Mrs Strode outside, in the backyard, splattering blood everywhere. 6 seconds later, Kara comes home from school. Michael cleans up the blood, puts the sheets in the washer, and puts Mrs Strode in the attic in the one minute 5 seconds that it takes Kara to walk to the back yard and look around.
Continuity mistake: The blood on Jamie's chin changes from shot-to-shot when she is being impaled on the farm equipment.
Plot hole: Why does Michael decide to kill Barry in the first place? Was he listening to the radio and offended by the comments that he made at the beginning of the film? (Though there is an explanation on the DVD's 'Producer's Cut', it remains a mistake.)
Continuity mistake: In the original film, the Myers house is very tall and thin, with skinny support posts on the porch and only 2 windows on the second floor. It is also lower to the ground. In this movie, the house (which is supposed to be the same) is considerably wider, with large supports on the porch and is higher off the ground. There is also enough room on the 2nd floor for the addition of an entire balcony.
Continuity mistake: At the bus station, Tommy finds a trail of blood left by Jamie, and also finds blood in the sink. Don't you think it would have been cleaned up by the time Tommy got there?
Continuity mistake: When Tommy is on the phone with Barry Simms, he holds the phone and types on his keyboard with his right hand simultaneously.
Continuity mistake: Throughout the film, Tommy Doyle is not wearing a belt. But suddenly when he gets to the Maximum Security ward in Smith's Grove, he is wearing a belt and it stays on for the rest of the film.