National Lampoon's Christmas Vacation (1989)

Revealing mistake: The family runs upstairs with the dog and the squirrel and then runs downstairs. You can see a cut in the movie, because the rug moves. (01:21:30)

Continuity mistake: After Clarke falls in the bush, the gutter repairs itself.

Continuity mistake: At the beginning of the movie, the Griswold family makes marks in the snow when they arrive at the tree which Clark wants. A shot later, the marks are bigger even though they haven't moved. (00:08:05)

Continuity mistake: When Clark is outside hanging the lights, he staples the sleeve of his shirt, under his wrist, to the eaves of the house. In the next shot, as he is pulling, the shirt is stapled over his wrist. (00:21:50)

Visible crew/equipment: Just as Clark begins his explosive argument, there is a shot of the family watching in horror, and the top of the set is visible at the top of the frame.

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Visible crew/equipment: When Ellen opens the door after Clark falls from the tree, there's a strange white thing visible for a few frames at the upper left of the door. Might be the hand of a crew member opening the door.

Continuity mistake: When Aunt Bethany asks "Do you hear it?", she leans forward in her chair. In the next shot she's suddenly sitting back, and leans forward again when she says, "It's a funny squeaky sound."

Continuity mistake: When the squirrel jumps of the Christmas tree it lands on the floor, but in the next shot it is on the coffee table. (01:19:50)

Revealing mistake: When Clark and Eddie push the chair to see what happened, the burned cat is only visible in closeups. There's also a blue object next to the couch that look like an iron that is creating the smoke effect.

Continuity mistake: When Clark's neighbours return home, the man says to Clark, "Where do you think you're going to put a tree that big?" The trunk is very large, bigger then Clark's feet. Clark replies, "Bend over and I'll show you." Then Clark cuts the tree trunk - it is very thin and easy for him to cut.

Audio problem: During dinner on Christmas Eve there is a shot of the cat chewing on Christmas lights. The sound of the cat chewing is a fraction of a second off.

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Continuity mistake: After the tree burns, Rusty says, "Dad's gonna flip out." Clark Sr.'s left elbow is close to and behind Rusty's head, but in the next instant shot of Rusty, Ellen, and Audrey, Clark Sr.'s elbow is not there.

Factual error: When Clark is sliding on the saucer, he shoots out a shower of sparks when he crosses the street. Those old saucers were made of aluminum, and aluminum can't create sparks like other metal does.

Continuity mistake: When Santa Clause's sled passes in front of the moon at the end, why is the sea so dark? It wasn't in previous shots.

Revealing mistake: After the squirrel lands on the coffee table, it rises up and twitches its tail in a mechanical motion, showing it is really a puppet.

Continuity mistake: As the shots quickly change from the front of Catherine and Rusty to their backs, Catherine is either holding Rusty tightly to her, loosely, or not at all.

Continuity mistake: When Clark is looking at his "bonus check", he's holding both the envelope and "check" together in both hands. In the next shot he's only holding the "check" in both hands and the envelope is no longer under it.

Continuity mistake: When Clark falls over while on the ladder, after ripping his sleeve off, his hands keep changing position on the ladder. When he first starts to fall, his right hand is gripping the side and in the next shot both hands are gripping the rung. In the next shot both hands are on the side of the ladder until the shot after he pushes himself away from the tree and they go back to being on the rung for a shot.

Continuity mistake: When Clark has the entire family outside to witness the lighting of the house, the positions of the in-laws change instantly from being clumped together to strung out in a line, depending on whether the shot is overhead or at ground level.

Revealing mistake: When the SWAT team arrive at the house, a member of the team runs towards the house and dives in the snow. However, instead of falling in the snow as you would expect, the white fabric on the floor bunches up.