Frida's messy room and missing book lead the gang on a ghost hunt that ends up putting their growing friendship to the test.
After a call from Frida, Hilda, and David rush to her house to help her with an emergency. Her otherwise perfectly neat bedroom is a huge mess, and she doesn’t understand what caused it. Hilda thinks a poltergeist is to blame, which upsets Frida since she’s running for class president and can’t use this distraction. Hilda suggests they clean up the room and put up a surveillance camera for the next night. David agrees to borrow his dad’s old camera and television for this.
The three friends clean up the room and install the camera, thought Hilda and David clearly do most of the work. When the work is done, Frida notices her favorite book, The Legend of Great King Condon, is missing. Hilda ensures her it will turn up. The following day, the room is a big mess again. As they watch the footage, Hilda and David notice Frida herself is the one who caused the mess. Frida admits, and tells her friends that until recently her room always cleaned up itself overnight. She thinks this is normal, but her friends point out that’s not how rooms work. When David mocks her for this, he and Frida get in a fight (with Frida using her wrestling skills to win).
Hilda still thinks a ghost is involved, but one that used to clean the room every night till he apparently quit. David ensures Frida she can get used to a messy bedroom, but Frida is extremely nervous about the reveal that she’s not as tidy and organized as everyone thinks, and it begins to affect her class president campaign. She is unable to answer questions from students, drops her paperwork, and she accidentally gives Mrs. Hallgrim the wrong homework. When she tells Hilda and David she’s going to drop out of the race, Hilda promises her to help fix the situation.
The three friends visit the library, where the librarian informs them ghosts often come back to collect personal items from when they were alive. The ghost that cleaned Frida’s room probably took the missing book since it belonged to him. Frida recalls the name Craigie Williams being written in the book, and the librarian immediately tells them where he’s buried in St. Guglows Cemetery. She also gives Hilda a book and wooden stick engraved with symbols for summoning ghosts, but warns her it could be dangerous.
That night, Hilda, Frida, and David set out for St. Guglows Cemetery. Frida and David get into another fight when David suggests Frida should learn to accept she’s not perfect. Hilda encourages David to go on, citing the incidents with the Troll Rock and the Marra as examples where Frida helped him. They find the grave and summon the ghost of Craigie Williams. He immediately recognizes Frida, and admits he cleaned her room every night since she loved The Legend of Great King Condon as much as he did. When he could no longer find the book however, he stopped coming.
Craigie doesn’t have the missing book, but suspects his sister Engilbjort does and angrily wakes her up from her grave. The two get in a heated argument, and when Frida demands her book back, Engilbjort challenges the kids to a wrestling match. Hilda agrees. Despite it being three against one, and Frida having a wrestling badge, they lose due to Engilbjort using her ghost powers to cheat.
Then the sun begins to rise and the ghosts have to retreat back into their graves. Seeing a chance, Hilda quickly lies down on Engilbjort’s grave so she can’t get back in, and refuses to move unless she returns the stolen book. Engilbjort reluctantly agrees. Except the book she gives Hilda is not The Legend of Great King Condon, but The Squire’s Folly. Engilbjort swears that’s the only book she took. Frida tries to persuade Craigie to keep cleaning her room, but he refuses.
The three kids thus return home empty handed. Hilda first takes a bath, feeling depressed that she failed Frida. Later, at school, Frida bails out of giving her speech for the Class President election. Hilda and David find her at home. Upset by everything, Frida lashes out at Hilda, sparking a heated argument between the two girls in which they call each other out on their shortcomings. It ends with David and Hilda leaving in anger, but not before David tells Frida she could learn to clean her own room. When they’re gone, and Frida is lying on her bed, a Nisse suddenly appears from underneath the bed and takes another one of her books.
- Frida's mom
- Ms. Hallgrim
- Principal Magnusson
- The Librarian
- Trevor (cameo in the school)
- Trevor’s friends (cameo in the school)
- Tontu (Frida's House) (cameo at the end of the episode)