During the Summer holidays, Zatch and gang decide to head for Fuji Mountain for a picnic gathering. There, they encounter a girl with a white magical book. Her name is Kotoha and her book has a message saying that Zatch's mother is located a cave in the forest. However, when they eventually found the cave, there was already a blond-haired youth by the name of Wiseman. In order to rescue Wiseman, Zatch and the others attempt to proceed into the depths of the cave and stumble upon the entrance to another world. Soon later, the strongest warrior, the Black Knight, appeared before them. Thinking that Zatch was the one who stole the 101th magical book, the Black Knight started to attack them. Zatch and Kiyo have to find the real criminal in exactly 24 hours, or else they will be stuck in the al