Revealing mistake: How on Earth can Selby get those skin tight T-shirts over that huge cast on her arm? They cannot possibly stretch any more than they already are - look at the scene where she and Eileen are checking the mail. There is no way that sleeve would fit over the cast without ripping! It is well beyond the capacity of that tight T-shirt to stretch to that extent! Obviously Christina Ricci had the cast fitted after she was in costume.
Revealing mistake: When the 54th Mass. marches past a liberated plantation some black children wave them on. One of them is wearing a digital wristwatch.
Revealing mistake: When Frank kicks the grocery store owner in the face twice his kicks miss by far.
Revealing mistake: When the kids step out of the water and walk towards the house, the floor is already soaking wet from previous takes.
Revealing mistake: At the end, Wallace's friend is charging in slow motion, and if you look closely you will see his battle axe flopping around like it's made of rubber. (02:49:50)
Revealing mistake: In the David Letterman scenes, Paul Schaeffer's head is shaved, which he just did recently (maybe within the last year to year and a half). (01:15:00)
Revealing mistake: Several maps of Europe shown in the film have Germany divided into East and West, and show national borders from 1945 onwards.
Revealing mistake: In the scene where Lorraine Bracco points a revolver at Ray Liotta's head, after Ray Liotta turns the tables and now points the gun at Lorraine Bracco as he gets up and walks away you can see Ray Liotta steps on Lorraine Bracco's hand and she opens her mouth wide like shes screaming but it must have been cut from the audio, as Ray walks off camera his expression changes to show that he knew he had accidentally stepped on his co-workers hand.
Revealing mistake: When Homer placed the rocket on his fence and lit it his friend asked "Should we get behind somethin'?" That's when the rocket explodes. When you see them fly back you don't need to slow motion it because you can clearly see the wires attached to their backs.
Revealing mistake: When Chris and a companion are on a rooftop in the midst of clothes lines with sheets hanging to dry, all the sheets have creases indicating they had been recently unfolded or removed from original packaging before being hung on the lines.
Revealing mistake: Early in the film, when Hughes and another guy are walking past one of the replica WW1 aircraft used for the "Hell's Angel" scenes, you can see the ends of the cylinders of the modern air cooled engines they used to power it. The original aircraft (SE-5A) used a water cooled V8 which wouldn't have been visible.
Revealing mistake: When the farmer is going to shoot the sign the bank put up, you can very well see the mark where the hole is going to appear.
Revealing mistake: The film is set in 1997 the year of Diana's death. However there is a scene in where Tony Blair is being driven in a car and you can see a Mercedes through the rear window with an '02' number plate indicating a 2002 model vehicle.
Revealing mistake: Towards the beginning of the movie, young Alexander tames a horse and then jumps on the horse and rides off. He is supposed to be riding bareback, but in one of the shots from a distance, you can tell that the actor's feet are in stirrups.
Revealing mistake: The scene in the sanitarium where Nash is given the insulin shot (usually done with a dummy retracting needle) you can see the tip of the needle slide along the skin as it is supposedly withdrawn. (01:19:05)
Revealing mistake: When Natalie Portman's character is about to be executed, if you look at the wall behind the executioner, you can see a modern metal drainpipe.
Revealing mistake: In the scene were Charlton Heston has just said goodbye to Sophia Loren and is about to ride off with his followers (last scene just before the set intermission in the film), you can just make out a tiny little red automobile riding through the landscape in the background.
Revealing mistake: When Maturette dies at the end he cannot close his left eye all the way because of the totally noticeable fake contact lens he is wearing.
Revealing mistake: When Mary of Guise is found dead by her nephew, he lies her down and puts his head on her chest. As he comes down, her eyes slap shut! If she were dead, they would remain open.
Revealing mistake: The ball Lou Gehrig hits that smashes a window doesn't come off his bat. It comes from behind him.