Stupidity: If the family is planning a big shopping trip, why would Clark still be in his morning clothes and busy putting presents in the attic as if he didn't know? And why wouldn't have anyone told him or reminded him before leaving the house? It just seems like a plot device using the foolishness of the characters to have him trapped in the attic.
National Lampoon's Christmas Vacation (1989)
1 stupidity
Directed by: Jeremiah S. Chechik
Starring: Chevy Chase, Juliette Lewis, Diane Ladd, Beverly D'Angelo, John Randolph, Johnny Galecki
Factual error: In the scene where Clark is working on the lights the full moon is shown. This is December 14th according to the advent calendar. On December 24th when Santa's sleigh goes sailing over the moon, it is still full.
Clark Griswold: [reciting 'Twas the Night Before Christmas.] When what to my wondering eyes should appear, but a miniature sleigh, and...and Eddie with a man in his pajamas and a dog chain tied to his wrist and ankles. What the...?
Trivia: Clark Griswold in the attic watching old movies dressed in a woman's turban and gloves to keep warm is not only funny but a reference to the Norma Desmond character from "Sunset Boulevard", who watches her old films to remember her Hollywood glory days.
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