It’s Halloween day and when the Bubigirls are in the shop they hear a strange sound coming from the storehouse, at first they think that it’s a joke but when they hear it a couple of times, they become afraid… There’s a monster in the storehouse! Moreover, there’s no sign of the Little Witch neither Lil Pop so they deduce that the monster has kidnapped them. They run to the Bubilab to ask for help. In there, the Bubiloons are having a scare contest so they don’t pay much attention to them until finally, not believing the story, they decide to go to the shop to see what is happening. The sound starts again and everyone is very scared when suddenly… the Witch appears through the door and asks them why the party isn't prepared. The Bubigirls tell her that it’s because there’s a monster. The Witch incredulous opens the storehouse door and she finds Lil Pop making the strange sounds the girls have been hearing all day (he had got tangled in some garlands and he couldn’t get out of there).