Factual error: The film takes place in a private boarding school the 1950's, however one of the students is studying from a 1980's chemistry textbook.
Factual error: At the end of the film Rainwood has established his innocence of the drug charges and is happily back at work as a senior mechanic for a large airline. However, part of the sentencing and plea bargain protocols at his arraignment is his previous conviction on a lesser drug charge years before. It goes without saying that he did not advise his employers of this when he started work for them - no airline in the world (even pre 9/11) would hire someone with a drug conviction on their record! Now this is out in the open the airline knows that Rainwood is a convicted drug user (on the lesser, legitimate charge) and that he lied on his original job application. They wouldn't hire him again to sweep the floors.
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.
Continuity mistake: During the first car ride scene Harry is spitting the seeds out the window. One of the shots shown of the car from the outside shows the window still up after he has rolled it down.
Continuity mistake: In the scene where Ouiser sits and lets out a belch, if you look in the mirror, you can catch her laughing.
Continuity mistake: Early in the film Bud throws his wedding ring down the latrine and then retrieves it with his right hand so it is covered with the blue disinfectant. In a (much) later scene, Bud has a blue right hand, despite not having had one in the intervening period. (01:44:48)
Other mistake: Sergeant Johnny Gallagher (Gene Hackman) and Lieutenant Milon Delich (Dennis Franz) are in a supposedly deserted building searching for a group of conspirators who plan to assassinate both the USA and USSR presidents. Delich finds a police colleague of his in the building, and Delich kills his colleague. When he fires his revolver, the sound of the blanks can be heard, slightly out of synch with the gun blasts on the sound track.
Continuity mistake: When Beck meets Webly on Christmas Day, Webly takes his glasses off and throws them on the desk, but in the next shot (from behind) he is still wearing them. (00:16:50)
Continuity mistake: When Lloyd calls Diane's house for the first time to ask her out, he gives her father his phone number as 555-1342 (several times), but later when Diane is reading her list of messages, Lloyd's number is listed as 555-2342. (00:12:40 - 00:15:50)
Revealing mistake: During the first shot of Larry being pushed out of the car, it's blatantly a stunt double who is taller, thinner and has shorter hair than the actor.
Revealing mistake: In the scene after the battle of Agincort, where Henry and his retainers are walking meditatively among the heaps of the fallen, if you look carefully, you will see one of the fallen with his head raised watching the procession. He then realizes that he is on camera and puts his head back down. It's near the edge of the screen so may occasionally be cropped.
Continuity mistake: There is no knife on the table when the wife enters the kitchen at the very end, however, she walks straight to Louis, hugs him and then magically a knife appears at the edge of the table which she picks up and uses to stab him (implied - the movie actually ends at that point).
Revealing mistake: On the way to the party, near the end, they are supposed to be in Alabama when the car gets pulled over, but the officer's badge, shoulder patch, and car all say Georgia State Police. (00:51:45)