Twas a long time ago, longer now than it seems, when a new tradition was born in the Fall of ’93. For those who’ve not wondered where The Nightmare Before Christmas came from, it’s time you begun.

Tim Burton’s popular stop-motion animated film, The Nightmare Before Christmas, opened in theaters October, 13, 1993. The release date was set just in time for the Halloween season, and the film received high praise from both critics and movie-goers. Since then, Burton’s famous Nightmare has become not only a staple movie viewed every Halloween, but has even managed to carve a place for itself among the traditional Christmas season movies as well.

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The story is about the Pumpkin King, Jack Skellington (Chris Sarandon/Danny Elfman) growing tired of the monotony of scaring people year after year in Halloween Town, and then trying to take the magic and wonder of Christmas for himself. Jack Skellington goes through an otherworldly, yet relatable journey of self-discovery, and falls in love with Sally (Catherine O’Hara) in the process, after he saves her from the Oogie Boogie man (Ken Page) and they help Sandy Claws (Ed Ivory) save Christmas.

While The Nightmare Before Christmas is indeed one of the most popular cult classics of its generation, many may be unaware of its origin story. Eleven years before the theatrical release, Tim Burton actually wrote a poem of the same title in 1982 while working as an animator for the Walt Disney Company. The idea was partially inspired by a mix of The Night Before Christmas by Clement Clarke Moore and How the Grinch Stole Christmas by Dr. Seuss. He originally pitched The Nightmare Before Christmas as a children’s TV special soon after writing the poem, but Disney passed on the idea at the time. Eventually Burton’s success with other ventures (namely Vincent) gave him the confidence to pitch the idea again, now as a feature film. Disney believed the content might be too scary for children, but they wanted to do the movie and released it through Touchstone Pictures, where production began in 1991. Upon reading the poem, fans of the feature film might find it quite striking how true to the source material the movie turned out to be. This is partially due to the fact that upon beginning production, the original poem was the only script they had to follow.

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“We had to start production without a script, which is insane,” Director Henry Selick told The Hollywood Reporter “We didn’t really know what we were doing, but we had total confidence and we had a huge amount of fun.”

Danny Elfman had created original music based on the poem, but the rest of the work was done as they went along. “We knew the story well. The first songs came in, and we basically just blindly, but very confidently, went into production,” said Selick. Even though there was a lot of creative work to be done while shooting, a time when most screenplay decisions have usually been made already, the production process was fairly smooth for a stop-motion film.

Due to the story’s intertwining of the Halloween and Christmas seasons, and even an ending in which Christmas is saved by Sandy Claws, The Nightmare Before Christmas can’t quite fit neatly into the Halloween movies box or the Christmas movies box. It now stands on its own as the most renowned, if not only, film to be a true two-holiday film that people annually watch during the entire Autumn/Winter seasons. Nightmare memorabilia can be found in many forms. From Pumpkin King Halloween costumes, to Jack Skellington Santas on Christmas sweaters, people love to be in The Nightmare Before Christmas spirit for as long as possible.

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