Continuity mistake: The film is set on the Western Front during WWI but was filmed in Ireland in 1965. As George Peppard is driving to join his squadron for the first time the camera pans the horizon and loads of houses can be seen to have TV aerials.
Continuity mistake: The cars change shape frequently during the movie. That depends on the fact that many scenes were filmed at real races, with real F-1 cars. The cars that the actors drove were, for the most part, disguised F-3 racers. There are at least three fake Ferraris, and they all look different. One of them seems to have been built to resemble a 1965 F-1, but altered to look like a 1966 model. The non-existent Yamura (built to resemble a Maclaren), that James Garner drives is actually two cars with different chassis, one of them seems to be used very little, except when it catches fire in a scene.
Continuity mistake: Throughout the movie Elsa wears a collar. In the scene where she runs away the collar is visibly in place - a few minutes later, when she's found with the elephant, the collar has disappeared.
Continuity mistake: In the scene where Paul Newman seduces Shelly Winters in the nightclub, they're dancing to the sounds of a brass band, even though the musicians are all holding guitars.
Continuity mistake: On the airplane, Rock Hudson takes a pillow from the stewardess, and puts it behind his head. They cut away to the stewardess, and back to Hudson, and the pillow is gone. They cut to the stewardess again, then back to Hudson, and the pillow reappears.
Continuity mistake: As George says "That you people are rearranging my genes so that everyone will be like everyone else" he puts his left arm around Nick. His hand, though is on the back of the sofa. Instantly in the next shot, however his left hand is now on Nick's left shoulder.
Continuity mistake: When Alfie helps a woman out with a doctor, it's raining, but when Alfie goes outside the rain has stopped and there's no water on the ground.
Continuity mistake: Alva walks Owen out of the railway office. They pass by JJ and the local manager sitting in the street having their lunch, but in a POV shot that follows, they have yet to move past them. (01:00:00)
Continuity mistake: Brutus, the Great Dane, is shown crawling from right to left on the ground near the edge of the planter. After a brief close-up of Mark, his owner, Brutus is shown crawling from right to left in the exact same spot again. (01:16:10)
Continuity mistake: When he's called in to see the Captain, Montag wears his wristwatch turned inward (with the face resting over his pulse point). Seconds later, though he hasn't touched it, the watch has rotated itself 180 degrees and is now on top of his wrist. (00:26:05)