Revealing mistake: At the beginning of the scene near the end of the movie with Lucius Malfoy fuming at Dumbledore in his office, Malfoy's hair is fanned back behind his shoulders. The lighting in the room illuminates the back of his neck, where you can see his real, short brown hair. (02:22:05)
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.
Revealing mistake: When Scooby, Shaggy, Mary Jane, and Daphne go crashing through the window while running from the two monsters, the falling glass and broken window frame pass right through the CGI Scooby. (00:42:30)
Revealing mistake: At the party someone asks Marcus his name and he replies 'Vincent' the actor's real name (Vincent Cassel).
Revealing mistake: When Becky meets Simon in the cube, they hug, then Simon literally stabs Becky in the back. As she falls down to the floor, her black shirt reveals not only some of her chest, but part of a black microphone wire. (01:15:15)
Revealing mistake: When Jason climbs onto the rail of the fire escape, it is not attached to the wall - intentionally, it has not broken - but then in another shot, two seconds later, it 'breaks'. It pulls out of a visible hole in the wall, although it was never actually attached and there was no hole before. (00:23:25)
Revealing mistake: When Clint Eastwood and detective Jay Winston are talking in her office she walks over to the blinds and touches the plastic piece that closes them but nothing happens, they stay the way they were. She does this twice. (00:25:46)
Revealing mistake: When Charlie is writing her letter we can see it through a hidden camera in the pen she is using. By watching the angle on how the camera would be attached to the pen we know that she would have seen the camera. Also her hand would be blocking the camera view, so we shouldn't be able to see anything at all. (00:30:30)
Revealing mistake: When John goes to close Gordon's eyes, as he lowers his hand, you can see him close his eyes on his own.
Revealing mistake: When the coroners are taking Kemosabe's body to the hearse, the one who falls over the porch wall is wearing calf padding which can be seen bulging under his pant leg before he falls.
Revealing mistake: The alarm clock stops on its own after just 9 seconds of beeping. Real alarm clocks go for longer / forever to make sure you're awake. (00:06:05)
Revealing mistake: When Anderton first sees himself killing Leo Crow in the precog vision, pay attention to the shot when he says "no". The reflection of Jad in the Hi Tech screen doesn't match with his movements.
Revealing mistake: In the scene where Joey is arrested, they handcuff him. When the police pulls him on his feet, you can see that the handcuffs are not on, but the officer is just holding them. (01:36:05)