Continuity mistake: In the beginning of the movie, Laurie runs into Tommy while she is walking to school, meaning that they live near each other; however, later on in the movie, when Laurie has to babysit Tommy, Annie has to drive her to Tommy's house, which is located on the other side of town.
Suggested correction: The film never says Tommy lives on the other side of town. They were only driving so long as an excuse to cruise around, smoke weed and kill time. Loomis later tells Sherriff Brackett that he's walked 3 blocks from the Myers house and soon after that we see him arrive at the Doyle house, still on foot. Since we know the Strode and Myers houses are within walking distance of each other, we also know the Doyle and Wallaces aren't too much further away.
Earlier on the walk home Annie says the Wallaces are leaving at 7. She later calls Laurie and says she will pick her up at 6:30. Using those times, the ride couldn't have taken for than 30 minutes, part of which was occupied by the stop at the hardware store (when it's still daylight). There's really no way to reconcile this timeline.
Plot hole: When Laurie and her friend see the Sheriff in front of the hardware store, he tells them someone broke in and stole "A Halloween mask, some rope, and a couple of knives." Without someone doing a complete inventory of the store, there would be no way to know the specific items that had been stolen, especially when they are such commonplace things as knives and rope in a hardware store.
Suggested correction: Simple, he watched the security footage.
Before shutting off the alarm? Store video wasn't really a thing in a small town store back then.
Visible crew/equipment: When Laurie tries to escape Michael from the kitchen, she breaks the glass. You can see a second hand break the glass in front of Laurie's.
Suggested correction: You are incorrect, but it's an understandable mistake to make because the scene is very dark. It's hard to see, but Laurie actually uses both hands to break the glass... she puts them together and then slaps them through the window in a quick, fluid motion. (If you go through frame-by-frame or in slow motion, it's much, much easier to see.) That's why you're seeing two hands. It's not a crew member's hand... it's Jamie Lee Curtis' other hand.
Revealing mistake: When Michael cuts Annie's throat, notice there's no visible cut or blood at all. When your throat is cut blood is going to pour out.
Suggested correction: True, but the view we have is distorted because it's shown through the windshield in a dark garage. Blood most likely poured out, but we don't see it because of how it's shown to us.
In the documentary, John Carpenter specifically stated that he left out of the gore on purpose. He wanted to film the movie so that the viewer would have a "mental image" of the kills without all the blood. He wanted it to be left to the imagination of the viewer.
Continuity mistake: In the beginning of the film when Michael is walking through the house, the clocks have different times on them. After he walks by the clock in the living room, it says 9:40. Seconds later, it strikes ten times.
Suggested correction: This scene jumps ahead as Michael was in the living room waiting for them to finish having sex and the boyfriend to leave.
Continuity mistake: When Laurie, Annie and Lynda are walking home from school, the part where Lynda walks to her house you can see the station wagon on the side of the road behind them. A few seconds later it has moved up the side of the street.
Continuity mistake: At the beginning of the film the Myers' house is within walking distance of the Strode house, both of which are on one side of town, while the Doyle and Wallace houses are on other considering the driving distance Annie and Laurie had to drive to get to them. But at the end of the film somehow the Myers' house is now within walking distance of the Doyle and Wallace houses.
Suggested correction: Annie and Laurie took so long to get to the Doyle and Wallace houses simply because they were cruising around town, giving themselves enough time to smoke Annie's weed. After they leave the hardware store when the sun was setting, they continue killing time. That's why it was completely dark by the time they arrived at their babysitting jobs; they didn't drive directly there. Remember also, Tommy walks to school too. If the Strode and Doyle houses were truly a long drive from each other, he and Laurie would've never crossed paths earlier that morning when she drops the key off. All the characters' houses in the film (and both schools) are within walking distance of each other.
