Danny Fenton hates Christmas. When he accidentally destroys the only copy of a ghostly Christmas story, the book's author, Ghost Writer, 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, Ghost Writer 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 Ghost Writer, he is surprised to find his old ghostly enemies in a giving mood. Danny enlists them to help him defeat Ghost Writer and restore the spirit of Christmas to Amity Park and, perhaps, to his own heart.

Skulker's on a looting spree, snatching up a number of seemingly unrelated items. Unfortunately, Danny's attempts to stop him are thwarted by the well-intentioned meddling of Danny's new sidekick: Jazz. However, Danny didn't ask for -- and doesn't want -- Jazz's help, and after a series of humiliating mishaps, Danny blows up at his sister. In response, Jazz runs away from home... to Vlad's castle in Wisconsin! But it's only a ruse. Jazz soon manages to break into Vlad's inner sanctum and discovers that he has been using Skulker to collect the items necessary to upgrade the Fenton's stolen Ecto-Skeleton. When Danny arrives at the castle, Vlad makes Jazz don the improved battle suit in a no-holds-barred fight against Danny Phantom!

Technus is back, with a new plan to beam himself up to a super satellite and take over the world, and he's going to use Axion Labs to do it. As Danny Phantom battles Technus, Danny Fenton begins battling his feelings for Valerie, whose dad is back in charge at Axion. Sam and Tucker are surprised when Danny confesses he's thinking of asking Valerie to go steady. Unfortunately, as Technus puts his plan into action at Axion Labs, Valerie realizes her role as ghost hunter is putting her family and friends in danger. Can romance work between two kids with secret identities, or will the ghost boy and the ghost hunter end up breaking each others' hearts?

As one of the weakest ghost in the Ghost Zone, the Box Ghost attacks with every "deadly box" he has in the human world, but is easily defeated by Danny. He then makes a plan: he will use "Pandora's Box", the most powerful box ever created, and will use the evil and deadly powers inside it to attack Amity Park. Now Danny must find the only one able to save the day: Pandora herself!

Danny, after being publicly shamed by Vlad's new ghost hunting team, wants to be normal again. So he gets rid of his powers by reactivating the Fenton Portal after Jack dismantles it for a software upgrade. However, an asteroid made of Ectoranium threatens the Earth, and Vlad - after revealing to everyone that he is Plasmius - fails to stop it. The world now relies on a powerless Danny to get help from the ghosts in the Ghost Zone!