John Carpenter's 1978 Halloween while a spooky season classic and a must-watch every Halloween night — it was also on a tight budget. And although it earned close to $70 million against its $325,000 quota, small budgets can come with small mistakes.

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It's not uncommon in 70's and 80's slasher films to have continuity issues or even plot holes, and the original Halloween is no exception. From weather woes to mask mishaps, the film that launched the murderous career of Michael Myers is filled with minor errors only the eagle-eyed horror fanatics have spotted.

California Drivin'

Cars Halloween

Halloween takes place in the fictional town of Haddonfield, IL. It's where Michael Myers (Nick Castle) murdered his older sister, and later where Laurie Strode (Jamie Lee Curtis). In the scene where Laurie and her friend Annie are walking home from school, Laurie spots Michael creeping behind a hedge in his mechanic-and-William-Shatner-mask get-up. But when Laurie gets closer to the hedge, a cloud of smoke breezes by the camera.

John Carpenter himself admitted in bonus commentary that he was smoking a little too close to the camera while they shot that scene, thus his cigarette smoke was forever captured in the movie.

All Masked Up

Michael Myers Halloween

It's sometime between after school and sundown when Laurie and Annie are on their way to babysit, and they happen upon the convenience store's ringing alarm and Annie's cop father. With the alarm still sounding behind him, he informs the girls of a burglary that included a Halloween mask.

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So, why is it that this theft seemingly just happened — judging by the ringing alarm — yet when Michael shows up outside the girls' school and appears to Laurie out the classroom window, he's already wearing his famous mask?

From Wet To Dry

Halloween 1978

Because films are not shot chronologically scene-by-scene, it's easy to let some continuity errors slip by, like rain-covered pavement that miraculously dries from one scene to the next.

When Laurie is walking home from school with her friends on Halloween day, the sidewalk is wet in one scene, then appears like it never even rained in the next.

Leave The Light Off

Michael Myers CLoset Scene Halloween

One of the most famous scenes from the film is when Laurie hides in the closet, light off and a metal coat hanger as her only defense. When Michael finally barges through the doors and ends up turning the light on, he makes it not-so-subtle when he, in the midst of his struggling, grabs the pull-string and turns the light back off.

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It's unknown how much of a flub this really was from a filming standpoint, but watching Michael Myers focus more on turning a light off than murdering his victim always offers a good laugh at the most inappropriate moment.

Ain't No Mountain

Dr. Loomis Halloween

When Dr. Loomis arrives at a payphone (remember those?) and calls the Haddonfield Police upon Michael's escape, Loomis' frantic state is contrasted by beautiful mountains painting the background scenery.

It's understandable, considering this scene was shot in the City of Industry, CA, known for its surrounding mountains. But those mountains would never be in Haddonfield, as Illinois doesn't actually have many mountains.

Doorknob Drama

Tommy Doyle House Halloween

One of the biggest mistakes in this movie is one you need to keep your eyes peeled for. When Laurie runs back to The Doyle's house, banging on the door for Tommy to answer while Michael looms behind her, the doorknob is located on the right side

of the door.

But when the scene changes to Tommy opening the door from the inside, the doorknob is located also on the right side of the door, when it should be located on the left to align with it being on the right on the outside.

A Mistake For The Ages

Young Michael Myers Halloween

The entire town of Haddonfield knows that the infamous Michael Myers was 6 years old when he committed his first murder. And when exactly 15 years to the day goes by, Michael is now 21 years old when he escapes the institution and embarks on his murderous rampage.

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However, when the credits roll to that famous John Carpenter score, Tony Moran's present-day Michael is credited as being 23, not 21.

Not-So Knives Out

Michael Myers Halloween

One of Michael's best killings in the film was the way he murdered Lynda's boyfriend Bob. Appearing from the dark, Michael rams his butcher knife into the teen, stabbing him all the way through to the wall and allowing Bob's dying body to hang there.

It makes for an iconic slasher moment, but in actuality, a butcher knife would never be long enough to impale someone's body then go through a wall, and definitely would not have the strength to hold up a corpse.

'Halloween's' Biggest Fan

Laurie Strode Halloween

After Michael's break-in when Laurie is crouching on the floor beside the couch, the wind outside is ruffling the curtains just before she stabs Michael in the neck with her knitting needle.

But in a later scene, the movie's biggest fan appears in the shot — literally. A large fan can be seen from behind the ruffling curtains, clearly controlling what's supposed to be the autumn winds.

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