Magalie reluctantly goes to spend the summer at her godfather Hector's motel. She is brooding: what will she do in Bouillon? The mayor, Colette, proceeds to inspect the Motel in the hopes of finding a reason to condemn it.
Magalie finds an old doll and decides to change its batteries. The doll then comes to life and addresses Magalie, who panics. Strange phenomena seem to overtake the electric appliances.
Magalie and the monsters are trying to play Monstropoly, but the monsters just want to play by their own rules. Magalie gets frustrated with trying to show them her way to play.
It's the official reopening of the Motel of Bouillon. Unfortunately, Hector is sick and Magalie has to take charge to get everything ready for the clients. To better serve them, Charles buys an electronic interpreter.
Magalie has hired Hughes, a specialist in the hotel industry, who promises a free computer to anyone able to pass his training. But Hughes doesn't plan on giving away his computer easily.
The monsters are consuming a lot of electricity at night, and Colette decides to find out why. She visits the Motel for a spa day and spends the night for observation purposes.
A community garage sale is taking place at Bouillon, and Magalie and Kimi are competing against Colette to see who sells the most. Charles looks into getting a new encyclopedia.