Daniel "Danny" Fenton is the titular protagonist from the Nickelodeon animated series Danny Phantom. He is a teenage boy who, due to an accident involving the "Fenton Portal" built by his parents, had his molecular structure infused with ectoplasm, turning him into a half-human and half-ghost hybrid. In his ghost form, he is Danny Phantom, an extraordinary spectral superhero with a ghostly array of other-worldly powers, whose primary goal is to save the citizens of Amity Park from the dangerous ghosts coming through the Fenton Portal.
Danny's only appearance in a Christmas special was, naturally, the series' Christmas episode "The Fright Before Christmas!" As it turns out, Danny actually hates the holiday season because every year, his parents, Jack and Maddie, always argue about the existence of Santa Claus, and these arguments have always led to Danny suffering traumatic childhood memories. Danny goes to the Ghost Zone to reduce his stress by destroying Christmas items, but in the process, he accidentally destroys the Ghost Writer's manuscript, The Fright Before Christmas. When Danny shows no remorse about this due to his holiday hatred, the Ghost Writer gets revenge on him by starting work on a new poem and traps Danny and everyone else in Amity Park in it, making anything he writes come true until Danny learns his lesson (and as a result, everyone is talking in rhyme).
The Ghost Writer gets Danny in further trouble by making monstrous armies out of the mall's reindeer, everyone's holiday presents, and all of Amity Park's Christmas trees, and each time Danny defeats these, it only gets everyone in Amity Park angry at him for supposedly ruining Christmas. Danny returns to the Ghost Zone to confront the Ghost Writer, getting unexpected help from his usual enemies (who are holding an annual truce for Christmas), and destroys Ghost Writer's keyboard, but it still does not undo the spell GhostWriter has cast, because Danny still hasn't learned a lesson. Upon returning to his world, he finally expresses guilt over ruining Christmas for everyone and, along with his friends Sam and Tucker, as well as his ghostly foes, return all the holiday items to their rightful places, thus finally restoring Christmas to Amity Park and also breaking Ghost Writer's spell.