Braveheart
In Braveheart, medieval Scottish patriot William Wallace is often seen sporting a kilt. The Mel Gibson-directed flick is set in the year 1300, but kilts weren't even introduced until the sixteenth century. Whoops!
The Hurt Locker
In The Hurt Locker, one of the soldiers mentions uploading a video to YouTube, which was launched in 2004. The movie is supposed to take place the following year in 2005.
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