Continuity mistake: Hooper wears rimless eyeglasses, with the arms either attached at the upper corners of the lenses or at the sides of the lenses. If this didn't happen between shots within the same scenes, it could be presumed that Hooper has two different pairs of glasses and switches between the two, but they do indeed change between shots, such as when Mrs. Kintner slaps Brody, or even later, on the Orca. (00:36:05)
Visible crew/equipment: In the scene where the knights are attacked by the killer rabbit outside the cave, you can see the boom mic at the top of the frame.
Revealing mistake: When the stripper appears from the changing room during the cabaret scene, the stripper music is heard, but if you look carefully the tape recorder which is supposed to be playing the music is not actually moving.
Continuity mistake: When Mc Murphy is strangling the nurse at the end, from above his hat is lying on the floor, but when you see the shot from her angle, he is wearing it again. (01:56:55)
Continuity mistake: George's collar on his leather jacket is sometimes up, down or somewhere in between, in successive shots within a particular scene, depending on the camera angle. Additionally, his long neck scarf changes position numerous times, in shots following one another within the same scene too. One example is in the salon with Felicia and Jill. (00:18:20)
Other mistake: There's a horse that has apparently ridden up a cliff, and an electrical burning brand that can be changed onto different flame settings.
Revealing mistake: As Machine Gun Joe runs slowly runs over a fisherman in a small brook, he stops and "peels out" on his head. You can see a film crewman in the driver's seat doing the actual carnage.
Continuity mistake: At the Zurich sanction when Jonathan kicks the killer out of the window, just before he kicks him, look at the window. This window has two panes of glass that open outward, with the latch in the middle, but a view from the outside shows that it's a single window with one pane of glass in it, not big enough for two panes. (00:21:20)
Continuity mistake: Near the end, Sam Clayton is nearing the finish. The audio leads you to believe that the horse is breathing VERY hard, but when the camera shows the horse, the nostrils are NOT flared as they would be on a horse that has been run to exhaustion (or even down the block). Also, the people filming this scene obviously have no clue about the nature of sweating in horses. They showed "lather" all through the horse's mane. The ONLY places horses will lather while sweating is where something is rubbing, i.e. underneath the saddle, the bridle or breast collar, where the reins rub on the neck or between their back legs.
Factual error: While Stanley Kubrick boasted about the authenticity of the candlelit interiors, he must have missed the little drawing of a steam train on a period map - 40 years before trains were invented.
Factual error: Two passengers play a piano/vaudeville routine in the lounge for the officers and passengers. During its initial season (1936) Hindenburg had a lightweight aluminum baby grand piano on board. However, passenger accommodations were expanded over the winter of 1936/37 and the piano was removed. There was no piano aboard Hindenburg on her fatal flight in May 1937.
Revealing mistake: Near the end of the movie in the shot when Giorgio Perozzi is dead on his bed you can see him breathing twice.