Recently in National Lampoon's Christmas Vacation Category

Look at the ceiling in the Dinning room near the end of the movie. Its not a full finished ceiling. You can really notice it the time that Clark (Chevy Chase) is walking out of the room right after the big Squirrel Incident. He opens the front door to get the squirrel out and then goes in the dinning room to check things out. From everything breaking in there when the dog chasing the squirrel through the house. You really notice when he walks out of the room at that time and a few seens after that too. Most of the other rooms have nice ceiling but not this one.