Best horror movie mistakes of all time

Audio problem: After the aeroplane crashed, a dinosaur stepped over it and the windows shattered making the typical sound of made-of-glass things when broken. They are made of plexiglass (a sort of fibrous plastic).

Continuity mistake: Throughout the entire film the tattoo on George Clooney's neck moves position and changes shape.

Plot hole: The must be a lot of dumb scientists in Sebastian's lab. While defibrillating the invisible gorilla, (s)he becomes completely visible for a moment. However, not once do the scientists consider that applying a mild electrical shock to the system renders the invisible animal visible again - that electricity may be the key to the whole invisibility problem. They don't even comment upon the fact that the gorilla does become visible.

Revealing mistake: In one shot when the boat is pulling away from the waterfall, you can clearly see that the shot is the same one they used earlier in the movie. The water from the waterfall now is going up the cliff! They have just put it in reverse.

Continuity mistake: If you look carefully at the monster (Frankenstein) you will see that his face is different in the ending scenes. The reason is, during the movie you see the monster take the woman doctor and throw her out the laboratory window. You then see the monster kind of stumble, which he really did and broke his ankle. So in the final scenes they replaced Lon Chaney Jr. as wolfman with a stuntman, and Lon Chaney Jr. finished the movie as the monster.

Continuity mistake: In the British Museum, when Rick and Ardeth are saving Evie, Rick gives her a .45 pistol and they start to shoot the guards, her pistol fires once and the slide locks back meaning the pistol had no ammo, but she keeps firing as if the magazine was still full. (00:39:47)

Other mistake: At the carnival, you can see an African-American man staring at the camera for a while. I am unsure if he is a crew-member watching over the scene, or if he is just an extra trying to get onscreen.

Revealing mistake: In the scene when the main character is in the library on the internet, she goes to a couple of websites. When the shot shows the URL up top, it is C:\windows98\mydocuments\etc.html. Instead of actually searching on the web they used a premade html page and accessed it from their computer.

Audio problem: When Sidney comes running to the house and she sees Dewey come out with the knife in his back she screams "Dewey!" but her mouth says "no!" (01:23:45)

Continuity mistake: When Frost has the head pure-blood vampire on the beach, after he pulls out his first vampire tooth you see blood all over his mouth, but when it shows the closeup of him pulling out the other tooth, there is no blood. (01:04:22)

Continuity mistake: When Annie and Laurie leave the hardware store to go to their babysitting jobs it is broad daylight. When they reach the houses apparently just a few blocks away, it is already dark.

Continuity mistake: About 10 minutes into the movie, when the truck is chasing the 2 college students in the car and starts ramming them, the bumper and the trunk is smashed in. The shot changes and shows the car's rear end and it is in perfect condition. This repeats at least 3 times.

Deliberate mistake: Leaven spends too much time thinking about if 645 and 372 are prime numbers to be believable. But she knows the factors of 649 and the result of 26 to the power of 3 almost immediately. Plus anyone with any maths knowledge whatsoever would know that any even number (or one divisible by 5) can't be prime, so 645 and 372 could be dismissed without even thinking about it.

Continuity mistake: Right after Bennett takes off in the plane, Claire throws a gun to Alice. Between the slow-motion shots, the gun switches position in mid-air before Alice catches it. In the shot of Claire throwing it, the barrel is facing to the right, meaning that it should be facing to the left in the shot of Alice catching it. But it still faces the right when she does. (00:58:30)

Revealing mistake: Right after Nell sends Hugh to hell, Dr. Marrow and Theo come out of hiding behind a pillar. As Marrow puts his hand on the pillar, it squishes in as if it was made of foam rubber, instead of stone. (01:39:50)

Continuity mistake: During one scene in Camryn's Halloween birthday party (where she is wearing a silver mask), it is actually Tia playing this role instead of Tamera.

Continuity mistake: When Cheryl is running through the woods, she is wearing slippers that stay on up until she reaches the cabin door. However, in following shots, she is shown barefoot, and when Ash opens the door her foot is dirty as if she'd been running barefoot the whole time. (00:28:05 - 00:29:10)

Revealing mistake: When the UFO makes the huge flash that knocks everyone in the cemetery down, one of the police officers kicks a tombstone as he falls and it wobbles back and forth. (00:13:35)

Continuity mistake: Mr. Furlong pushes Zeke into the fishing tank and it breaks, soaking him from head to toe with water. Moments later they are walking out and he is dry.

Other mistake: In the slaughterhouse scene, after Harrigan has injured the Predator with his shotgun and Keyes reappears, the Predator throws its disc, and severs Keyes in half at the waist. We see his legs flop to the ground, and blood pour from above, but his upper half (torso, backpack and weaponry) mysteriously remain hovering out of sight. (01:21:50)