“The Nightmare Before Christmas” was filmed in a warehouse in San Francisco and as anyone who has ever been to San Francisco will tell you, temperatures can be all over the place. The warehouse didn’t have air conditioning, and on one particularly hot day the crew opened a garage door down at one end of the warehouse to try and get some fresh, cool air inside. Unfortunately, that led to one of the sets, well, melting. One of the sets (likely the forest that Jack wanders through on his way to the magical circle of holiday trees) was full of trees made of foam-core and they were affected by the change in humidity when the door was opened. The melting was very subtle, however, and Gavin explained that the film’s crew didn’t even notice until watching dailies:
“The trees melted. So, when you watch the scene, you’re like, what the hell’s going on? What happened? And all the background trees are doing this throughout the scene because they’re melting and moving and all because of the humidity. So, that scene had to be reshot.”
While there is one very intentional dancing tree in “The Nightmare Before Christmas,” it probably doesn’t look great when your background trees are moving around at random. That’s more than a little distracting, but it’s good that it was only one scene, at least?