Factual error: Gorillas are almost exclusively herbivores. They have been observed eating small insects and grubs but nothing larger. So why does Isabelle eat a rat at the beginning of the film? The serum may have turned her into a crazed killer, as it does with Sebastian, but it hasn't changed the structure of her teeth and palate, biochemistry of her digestive system and so on, all of which would be required. She might kill or torture the rat, but she'd never eat it.
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: When they finally arrive at the bottom of the sewer, Eddie's bandage is on a different cheek. (01:59:00)
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: 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)
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.
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: He cuts a hole in her pants for insemination. When in the car moments before fighting the dog there is no hole.
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 the Senator is about to be sacrificed, the cloth on her mouth immediately disappears for a split second. (01:29:35)
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: 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.
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)THGhost