Twelve-year-old Nat, with help from family, friends, and his "pet" Woody, a wolf that turns into a boy, must face werewolves that have been altered as part of a dastardly plan.

A boy who lives with his eccentric grandparents near a strange, apparently cursed wood longs for a dog, but the strange creature finally found by his grandfather hardly fits his image of the perfect pet, and it grows stranger by the day.