It is Halloween night and two very different witches are preparing for the evening's festivities. While Karen, a young trick 'r treater, is putting on her witch's costume, a witch named Hexabell is whipping up a potion to turn a stray kitten into a Halloween cat —a cat with witchy abilities. Balancing on Hexabell's broom is not one of the things he can do, so he gets lost. When Karen finds the cat takes him home and names him Spook. Now Spook has a difficult decision to make: stay with the witch who game him his powers, or let go of his powers and stay with Karen and her family, who love him very much.