In order to get his life back as a wizard, Torok the troll plans to take over an apartment building. His first step is to possess young Wendy Potter . Her brother, Harry, is the only one who suspects something is wrong. Fortunately, neighbor Eunice St. Clair is a witch and not only believes Harry but also agrees to help him. Meanwhile, as Torok, Wendy starts transforming other building tenants into mythical creatures, and only Harry can stop him.