10+ Mistakes In 'Friday The 13th' That Slipped Right By You

So Brenda is tossed out the window. Hilarious and terrifying. Alice runs outside to see Mrs. Vorhees driving up in the Jeep.

How did she do that if she just tossed Brenda out the window?

When Ned is pretending to drown and Brenda swims out to save him, you can see they stay underwater for a couple of seconds.

That's until they're visually cued to come back up.

When Alice jumps from Mrs. Voorhees' Jeep, you can clearly see she's wearing a white elbow pad.

Presumably, it's to break the actress's fall, but we're not supposed to see that!

When Steve Christy is leaving the diner, he sees that it's raining outside. It's obvious to anyone watching that "The Rain" is just a sprinkler.

Darn low budget movies, always skimping on the rain!

During the scene where the kids are playing "strip Monopoly", Sandy gets behind the counter and you can see some customers leaving the diner.

You can also see a cameraman reflected in the window.

Yes, there is more than one in this movie!

When the kid is playing guitar, the sound coming out doesn't match the frets that he's playing. Truly a terrible affront to the moviegoers!

When Mrs. Voorhees throws Alice through the table, I bet you can't guess what you can see under it.

Go ahead, take a guess. If you can't figure it out, maybe check the title.

When Annie is talking to the dog, it's position changes a couple of times between takes.

This, folks, is why they say you should never work with children or animals in showbusiness!

When the kids are playing at the beach and Alice shows up, there is a towel underneath her foot. In the next shot, the towel has changed its position.

Perhaps it's a ghost towel?

When Alice finds Bill all hung up about his death (aha, get it? Man, I'm good) you can see him still blinking his eyes.

Don't worry Alice, he's still alive! You can save him!

When she's thrown through the window, she is facing to her right. Later, when Alice returns to the kitchen, she's facing her left.

The position of the wood and glass changes as well.

When Brenda hears a noise, she puts her book down next to the candle and goes to investigate.

When she returns, her book is on the opposite side of the candle.

At the beginning of the movie, Claudette and all the counselors are singing.

Claudette stops playing the guitar as they get closer, yet the audio for the guitar continues somehow.

Uh... Spoilers? I guess?

At the end of the movie, Alice cuts Mrs. Voorhees' head off. We see that the head falls in the wrong direction, considering the cut started from the opposite side.