Continuity mistake: When Sam is in his bedroom, after he finds the Cube sliver it falls and dramatically burns a hole through the floor into the kitchen. But Sam's bedroom is over the living room (there is nothing on the ground floor below Sam's elevated bathroom, and in the first movie Jazz hides in this open space), and the kitchen is actually located between the den and dining room, at the other end of the house. If they were to follow the actual floor plan of the house, the Cube sliver would have landed in the area of the piano in the living room, but where would the fun have been in that? (00:12:30)
Factual error: It is barely credible that a young Victorian woman like Elena would even think about wearing a goatskin miniskirt - exposing her legs in those days would be akin to walking about topless nowadays. Even if she did those bright yellow cotton knickers - gleefully visible in the scene in the beehive - are in no way from the 1860s. Her pants are a hundred years ahead of their time.
Factual error: When Ray leaves his wife Gina and his car is hit by the truck he should still be in England, but when he is being chased through the streets he is in South Africa, the cops in the car are not in English police uniforms or vehicle, police livery is incorrect, and all vehicles have South Africa plates, not English number plates.
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.
Continuity mistake: In the beginning, when Anderton arrests the jealous husband, he notes that he is being arrested on April 22 - that day - for the future murder of his wife and her lover. Later, while Anderton is jogging, we see billboards advocating a "Yes" vote on pre-crime on April 22. The next day, Anderton's boss Lamar notes that the vote is in a week, which would make it April 15, making the day that the jealous husband was arrested April 14, not April 22. (00:13:05 - 00:15:15)
Continuity mistake: In the end, when the President is visited by the X-Men, he receives a blue binder, which is laid in front of him on the table. When they have left, you see a shot including the President's desk, and you can see that the only thing he has on the table are some sheets of paper, stapled in the upper left corner, opened up. Then the shot changes to a close-up of the President, and then back again, and you see the blue binder in front of him, closed, and the papers have disappeared. (02:01:40)
Revealing mistake: In the swimming pool scene, when David is sitting at the bottom of the pool, you can clearly see a scab on one of his knees. (00:43:00)
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 Norman is getting ready to test himself, he lies down on the bed, fastens himself in and the doctor goes to the computer. However, when it shows him being brought in to the chamber he has several electrodes connected to his chest and head. (00:15:20)
Factual error: Fitch, who professes qualifications in biology, genetics and biochemistry, says that they made Sil female because she's a natural predator and so she'd be more docile. He should retake his finals. In every single species of predator on earth - every single one - the females are the hunters, aggressors and killers. The males may be socially dominant but they are the 'docile' ones. There are no exceptions - and no human DNA was used to create Sil - they used synthetic DNA based on the instructions transmitted to them.
Continuity mistake: In the exterior front shots of Elliott's house there are some significant changes to the landscape in different shots. For instance, the two lampposts at the bottom of the driveway change to an entirely different style in some shots, and the huge garden boulders repeatedly vanish and reappear. Also, note when Michael takes off on Elliott's bike to go search for ET, the in-ground lamppost that should be beside the mailbox has vanished, but it reappears when all the government agents are setting things up outside the house.
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 final battle, Wasp and Ant-Man are in the van trying to get the quantum tunnel operational. We cut back to the fight and we can see Ant-Man there too, fighting in his giant form. (02:22:20 - 02:23:00)
Factual error: Amongst the essential parts of a nuclear weapon's detonation mechanism is a radioactive isotope of tritium, which has a half life of just 12 1/2 years. The tritium in every nuke on earth has to be replaced every ten years or so. This is by no means unusual; there are other perishable parts including detonators made of conventional explosives which would be completely inert after a thousand years. After lying dormant with no maintenance at all for that amount of time the nuclear weapons the 'Man-animals' find would be big shiny paperweights and not much else.