These are the adventures of Elena Potato, who moves with her family to Old Mill Village, and Ezekiel Zick, whose father is missing and is affected by all sorts of allergies including one that allows him to see monsters. Together, they uncover the secrets of the world of monsters. Zick and Elena face terrible danger and lethal enemies, which they are usually able to overcome. They are aided by Timothy-Moth, Zick's "cat", who is found to be unusual in that he has his own powers and can speak; he turns out to be a Tutor and a guardian of the monsters that are detained and tutored for breaking the rules of their monster city, Bibbur-Si.