Jack takes Helena to the amusement park. Manfred shows the small cabin where the old man who runs the amusement park switchboard lives. Suddenly the cabin leaves.
Jack goes to the amusement park and meets the Wizard Igor Johansson. He gets to ride with the Wizard and Manfred up the amusement park tower. There Manfred shows his magic binocular.
Jack is teased by Janne Muskel, but comforted by Manfred who sends Jack to Knut the Mirrorman. He has been stupid to those who are different and has been enchanted by a mirror.
Jack gets ten kittens from his mother. He takes them to Manfred, who arranges a tea party in his workshop. All the new friends come, and even the angry Old Man in the cabin gets a taste.
When Jack and Helena arrive at the secret tree, someone has put up a sign that says "Forbidden!". They go over to the entertainment field anyway and get to attend the awarding of the Children's Nobel Prize. Even Jack gets a prize.
It's Lucia at school. Jack's elf costume is ugly and Miss Tipp cheats so that Helena can't become Lucia. But Manfred and the Old Man in the cabin comfort the children.
Someone has put up a sign by the secret tree that says "Giants forbidden!". Jack throws the sign into the river. Inside the amusement park, he gets to see Joe and Mary practice a scary number.
Someone has removed the secret tree, but Santa helps Jack and Helena enter the amusement park. They sneak away to Manfred's workshop. Suddenly the Overseer and Figge and Stigge appear.
Manfred calls Jack and tells him that the Overseer has taken the Rabbit and Betty, and that the Wizard is also gone. Jack and Helena decide to find out where they are.
Jack and Helena sneak into the amusement park even though the Pirate Queen and the Controller are there. Suddenly they discover the villains with the El-Iminator in full swing.
Manfred's workshop is empty, and Santa tells Jack that the villains have captured everyone. Jack sneaks off to the Pirate Queen's ship to find out what happened. Suddenly, the villains discover Jack.
The villains hold everyone prisoner in Giant Karlsson's giant cave under the amusement park. Helena and Jack decide to try to save them, and call on the Nun Sisters with the magic hunting horn.
The children have been given permission by Santa to bring the whole class to the amusement park. The children's new friends receive, and it will be a different class trip.
Jack and Helena bring Jack's parents and Helena's sister to the amusement park. All the children's friends are waiting in the stable. They have a wonderful surprise.