It's getting cold in the castle and Mamma Kicki finds a crack in the castle wall that needs to be repaired. Benny punches a hole in the wall with a hammer and it makes it start to smell disgusting in the whole castle
Saga invites her classmates Ida and Jonna home to prove that there are ghosts in the castle. The ghosts find the hole that smells and clog it with a lynx cat.
Why has the rat Peggy suddenly become so alert? Saga and Benny are also wondering if there might be something behind the hole in the wall. Saga's classmate Frans finds out the ghost secret
Benny decides to investigate the mysterious nut. It turns out to have strange properties. Later the ghosts snatch the nut and Benny who gets scared of the ghosts falls down the stairs but is saved at the last second by the ghost Staffan
Benny finds dust from Count Julius Von Dy. Marshal Gunnar Palmgren shows up and claims that Kicki's crown belongs to the court. Kicki is desperately trying to keep it.
Benny and Saga are present when they return the repaired skeleton to the school. Mother Kicki is forced to pay for it and chooses to keep it as a mannequin for her queen dress.
On Lucia, Jean and Staffan try to scare the family away so that they do not fall for the Count. No one gets scared - instead, Kicki decides to advertise for ghost hunters
Leif Olsson, Lillan and Ivar's father, comes to the castle and claims to be a ghost exterminator. In fact, his intention is to prevent any real ghost executor from accessing his old friends Jean and Staffan.
Saga, Benny and Frans follow in the footsteps of the skeleton count and discover a great secret. Leif shows Stig his latest ghost equipment which consists of two vacuum cleaners
The three explorers go down to a mine through the fireplace. Down in the mine they meet the count whom they "help". Leif performs a session with an impressed Kicki and a skeptical Stig, but it all goes badly
Saga, Benny and Frans go down to the caves under Greveholm on behalf of Dioda to stop the count and prevent him from finding all the "ggä" (as Dioda calls them). Above ground, Stig becomes jealous of Leif who is admired by Kicki.
Saga, Benny and Frans try to figure out how to get across the lake to catch up with the Count and save Dioda's gag. Leif demonstrates the skeleton trap. Stig does not think it works and decides to try it for himself
The count bursts past all the obstacles created by Dioda's people. His brutal advance makes the cave begin to collapse. Saga, Benny and Frans try to save Dioda's eggs before everything collapses.
Saga, Benny and Frans are stuck in the cave while the Count escapes with Dioda's eggs. Stig thinks he has proof that Leif is a scam, but the question is. Can ghosts get caught on film. Everything is put on its head when Leif's wife enters.
The count has managed to create a monster. Now he wants the rest of Dioda's eggs to build an entire army. Jean and Staffan guard behind the barricades. The children are preparing for battle. How to protect yourself from a grip?
A rocket from space lands in front of the castle. Dioda and her servants have come to get their eggs. The Count proposes to Dioda again. Kicki and Stig keep the ghosts Jean and Staffan trapped in a refrigerator.
Lillan (Olsson), Saga, Benny, Frans and Dioda go out into space to clear away the space junk and help Santa. Down on earth, the whole Olsson family comes to visit Greveholm