Frederik has invited the class to his yearly Christmas party. He and Josefine has become best friends, and has planned to join the dance competion together. They have been praciticing for months to win the big Christmas basked. Just before the competion begins, Josefine tells Frederik a big secret, which change the entire evening.
Frederiks world collapse when Josefine tells him that she has to change school. The sad news cause a lot of fuzz on the dance floor, when Josefine and Frederik suddently no longer is a couple. And to top it off, something strange happens, which cause the entire class to stop.
Frederik invites Josefine home, so they can prepare a presentation for the class. This is but a cover, since Frederik wants to try convince Josefine to stay. It turns out to be more difficult than he thought.
The class has to do presentations. Frederik has not been able to concentrate on preparing, and fears that Bertram will post his bad presentation on YouTube. His improvised presentation get a mixed reception from the class.
Caroline and Frederik tries to convince their teacher to allow them to use the class funds on the common Christmas party. Her only condition is that everyone needs to agree. Frederik has to be creative to get everyone to accept.
Martine and Frederik is in the forest to find a Christmas tree for the class. Frederik intents to spend the afternoon convincing Martine that the common Christmas is a great idea, but strange things happen in the forest..
It's December 1st and it's time to unwrap the first gift in the class. Caroline is the lucky one, but can't decide which gift to choose, and then a big strange gift appears. Who's it from? And what is in it?
Frederik and Caroline want to find out who is T.E.S. Frederik has a clear suspicion, but he need proof. Caroline suggest that they unwrap all the gifts, since they may contain another piece of evidence. Will they find anything? And can they get away with it?
Caroline and Frederik is in for a big scolding, but are saved by Bertram, who comes with important news: T.E.S. has been at it again, and this time he is after one particular student.
Frederik is forced to appologize to Martine by The Black Squad. A series of events make Martine and Frederik join forces in trying to figure out who T.E.S. really is. Frederik immediately let Caroline know about their new theory.
Frederik has set a trap in order to try to capture T.E.S. An argument med Josefine, forces him to let Caroline be in charge of the task. Will his plan succeed? Or is T.E.S. too sly?
Frederik is convinced that Mathilde is The Evil Santa. When he and Josefine is invited to her house, he sees the opportunity to snoop around, looking for evidence. Will he manage to expose Mathilde as The Evil Santa?
Frederik is sure that he has the evidence that will expose Mathile as The Evil Santa. A text from Josefine changes everything and suddenly everyone thinks that Frederik is T.E.S.
Everyone believes Frederik is The Evil Santa, and for the first time he feels what it's like to be the outcast. Mathilde is going to the principal to tell what is going on. What will happen if he believes her?
Bertram and Martine acuse each other for being behind the vandalism and the cause of Frederiks expulsion. In order to tell on the other they compete in becoming the Lucia Bride, since she has the microphone.
Charlotte has planned a treasure hunt for the class. Mathilde really wants to win, but her team is on a different mission. They want to find out who The Evil Santa is. An unexpected call from T.E.S. gets them closer to the truth.
Josefine, Bertram and Martine desperately tries to figure out why The Evil Santa has stolen the class savings. The Evil Santa agrees to tell them on one condition: That they all go on the class cottage trip. There's only one problem: Frederik is mad at everyone and won't go.