Danny Fenton hates Christmas. When he accidentally destroys the only copy of a ghostly Christmas story, the book's author, Ghostwriter, makes Danny hate the holiday even more by turning him into the main character of a brand new Yuletide tale. Danny is now trapped in a scenario where everyone talks in rhyme! With his magical Quantum Keyboard, Ghostwriter creates a series of catastrophes that threaten to ruin Christmas for all of Amity Park and pins the blame on Danny. When Danny goes into the Ghost Zone to confront Ghostwriter, he is surprised to find his old ghostly enemies in a giving mood. Danny enlists them to help him defeat the Ghostwriter and restore the spirit of Christmas to Amity Park and, perhaps, to his own heart.

Otis convinces his college buddies Donner and Blitzen to stop by the barnyard on Christmas Eve night. During the visit, Otis accidentally gives Santa a cup belonging to the sick Freddy.

The families escape to a mountain cabin in search of "the perfect Christmas". Things get a little crazy when Tommy and Chuckie lay traps for Santa and Chuckie's dad dresses up as Santa and tries to squeeze his way down the chimney.