Revealing mistake: Mirrors were used to make the corridors appear longer, early in the film when Brett is complaining to Parker about the way they are treated by the company you can see their reflections in the mirror behind them as they walk down the corridor. It's only for a second as they are moving off camera but you can see them in their white overalls.
Revealing mistake: When the taxi goes over the edge to capture Dr. Neville, you can see that the underbody of the car as it goes over is a flat painted surface and not the underside of what should be there (i.e., muffler, gas tank, etc.).
Revealing mistake: In the opening scene where the zombie kills Johnny. When they fall against the tombstone you can tell it is a dummy.
Revealing mistake: When the chair moves across the kitchen floor, Craig T. Nelson goes to investigate it (after it has stopped moving). He goes up to the chair and flips it over. If you look closely, Craig almost hits the camera with the chair's legs. You can tell this has happened because the camera moves up very quickly and Craig looks straight at the camera crew with very big guilty eyes. This is more easily visible on the widescreen version of the film. (00:33:30)
Revealing mistake: When Strahm's phone says "no signal" there is actually a three bar signal. (00:06:35)
Revealing mistake: In the beginning of the movie, when Michael removes the knife from the drawer, you can see the blade bend.
Revealing mistake: In the part it shows Ash getting sucked into the time portal you can see the wire he is hanging from. (00:02:45)
Revealing mistake: When the lawn mower the heroes send off as a diversion crashes you can see a wire pulling it. (01:01:30)
Revealing mistake: When Nancy is running up the stairs in her house to escape Freddy for the first time her foot hits the steps and go through the steps into some goop. Look at the steps above that step and you can see the pre-cut holes where the next sets of goop will be. (00:39:10)
Revealing mistake: When Ripley first burns the egg plants inside the nest, the Queen screams and moves her head. The steel rod used to hold the Queen's head to the rest of her body is easily visible.
Revealing mistake: When they are all in the camper van Tiffany gives Chucky a biscuit then walks away from him, from the way she gave him the plate, they would have all fallen off. (01:07:35)
Revealing mistake: After Dr. Lawrence cuts off his leg and is crawling towards the gun, if you look at his dismembered leg, you can make out the shape of his foot hidden beneath his ripped up slacks. (01:29:30)
Revealing mistake: When Bella sees Waylon's body being gurneyed onto the ambulance, Bella has a flashback of Edward's eyes being black. In the short snippet, you can see the rim of the contacts he's wearing. (00:45:15)
Revealing mistake: When Marion is driving her car through the night, she keeps looking at her speedometer. You can clearly see that the gear shift lever is in "park" as she is driving.
Revealing mistake: Just as Jacob enters Bella's room through the window, a stunt prop - white band on his right wrist - is briefly visible.
Suggested correction: There is nothing on his hand if you watch frame by frame.
Revealing mistake: When the crew are getting ready to load up the gold, one of the crew slams the crate lid making the gold bars "move".
Revealing mistake: When Solina is crawling on the wall, whenever she turns her head, her long hair turns with it, instead of falling freely downward toward the floor. (01:05:20)
Revealing mistake: Each crew member has a monitor on their spacesuits that they use whenever they are exploring the caves. Whenever the monitor is shown, each crew member's individual heartbeat is shown in the lower left corner of the monitor. But no matter which heartbeat is shown, every time a heartbeat on the monitors is shown, it is always the exact same heartbeat, despite the various changes in panic and stress throughout the movie.
Revealing mistake: When Sarah is making her way to the baby Stego, just before she gets on her belly and crawls closer to it, you can see the kneepads she has on.
Revealing mistake: When Chris is trying to escape out of one of the first floor windows, the shots you see from outside are of a stunt double with really bad frizzy hair. (01:14:40)