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.

manthabeat

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.

manthabeat

Continuity mistake: When the grandfather is sleeping in the top of the bunk bed, there's a cheesecake poster on the ceiling. When Clark falls through the attic floor onto the bunk bed, it's not there.

Revealing mistake: When Snots the dog chases the squirrel into the Griswolds' dining room, he barely brushes a high-back dining chair that immediately falls on its side. If you look closely, a string attached to the the right side top of the chair can be seen tightening which then pulls the chair down.

Continuity mistake: In the scene of Clark standing in the snow trying to figure out why his Christmas lights did not work, the paper he is holding in his right hand is mid torso to him, but in the next shot when Rusty leaves him, his right hand has instantly dropped to his side and he raises his paper-holding hand again.

Continuity mistake: When Clark, Eddie, and Catherine are admiring the Christmas lights of the Griswold house, Clark is very close to Eddie with his left arm draped over Eddie's shoulder, but the next quick cut to Clark when he says, "Eddie?", shows Clark further away and his left arm at his side, and not stretched out.

Revealing mistake: The stunt double for Nicholas Guest is obvious after Julia-Louis Dreyfus punches him. The hair style of the stunt double is different from Nicholas Guest's hair, which is heavily slicked back.

Continuity mistake: In the Christmas dinner scene, closeups of Rocky show his right hand raised to his face, but the overhead shots do not.

Continuity mistake: The first time Clark fails with the lights, Ellen's mother says she hopes the kids see what a waste of resources it is. During this scene the level of her martini changes.

manthabeat

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.

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.