Picking up right where The Spell of the Sorcerer’s Skull left off, this fourth book in the Johnny Dixon series finds Johnny acting very strangely. He has terrible dreams, he wakes up having sleepwalked, and he is acting mean to his friends Fergie and Professor Childermass. The spirit of the evil Zebulon Windrow has taken over Johnny’s body, and soon he is lying in a coma close to death. It is up to the professor and Fergie to save him, but that means going to the icy and dark Windrow estate, where the spirit of the evil wizard awaits them. Will the professor and Fergie get out with their lives? Will they be able to save Johnny’s? The world seems to be falling down around them.