Factual error: When the judge is interrogating Margaret, a very un-18th century filling can be seen in her teeth.
Continuity mistake: When the farmer threatens Henry VIII with a fork after he catches him in the barn with his daughter, you can see that Henry is holding on the fork and it is well away from his body, but in the next shot the fork is pointing near Henry's face.
Other mistake: When the Mayflower truck is on the move picking everyone up for the heist, a mysterious hole appears above the truck's cab, cut out in the letter "o" in "Mayflower" when Pop is picked up, that wasn't there a moment before, and then it vanishes. The same thing occurs after the heist, when the truck crashes into the police cars.
Deliberate mistake: While on the sideline during a game, Sayers tells Piccolo that he should ask Dr. Fox to give him something for his hay fever, and Piccolo heads back to the field. The next close up of Sayers is a flipped shot; note the "40" on his jersey. (00:41:55)
Factual error: The movie is set at Christmas 1933.The radio that Olivia,Grandma and Grandpa Walton are listening to is a Zenith model S-232 (either 7,9 or 12-tube) which was not made until 1937.
Factual error: There is a picture of Elvis in Jacy Farrow's bedroom. The film depicts a small Texas town in 1951 to 1952. Elvis' first recording was in 1953 and he did not become famous by any sense of the word before 1954.
Continuity mistake: During the wedding sequence when Walter Matthau is trying to force his daughter Mimsy out of the bathroom his vest is closed with his tie inside. The next second the vest is open. Then it switches back to being closed again.
Continuity mistake: At the end of John Pithiou's dinner speech there is a close-up on the black butler. In that close-up, the collar of his vest flutters, shaken by the fan activated by the other slaves in the background. In the previous shot he was in the same hunched over position, but the fan had no such effect - you can tell by the position of the slaves in the background that he is standing in a different spot even if he was not supposed to move. (00:20:35)
Audio problem: When the saxophonist talks to Eddie (Albert Finney) before joining his band, which has already started playing, the saxophone can be heard although the player has not yet joined them on stage.
Factual error: Raquel Welch is shown to have modern tooth fillings during the rape scene.
Other mistake: The escaping prisoners gain shoes when, for most of their stay in prison, they were barefoot.
Other mistake: At the very beginning of the film, we see Christie commit a murder at the end of the Second World War whilst wearing the uniform of a Special Constable. Christie served during the First World War, and he wears the ribbons of the 1914 or 1914/15 Star, the British War Medal and the Victory Medal on his tunic. Unfortunately, whoever put them on put the bar upside down - they read from left to right VM, BWM, Star.
Visible crew/equipment: When Miss Ewell is walking back along the bus, you can see the shadow of a boom mic.
Factual error: When Mission Control tracks the orbiting Apollo spacecraft, the ship's ground track up on the big map has it moving across North America parallel to a line of latitude. With the exception of orbiting directly over the Equator, this is impossible.