THE NIGHTMARE BEFORE CHRISTMAS, conceived and produced (but not directed) by eccentric filmmaker Tim Burton, is now a beloved dual-holiday classic. But the 1993 animated musical faced numerous challenges, from  creative clashes and the technical complications of the stop-motion process to the story's originator occupied making another feature at the same time. Hop in the sleigh with Jack and find out "WTF Happened To THE NIGHTMARE BEFORE CHRISTMAS!"