When Johnny Dixon takes a tiny skull from a haunted dollhouse, demonic forces are released, capturing Professor Childermass and leading Johnny on a harrowing chase to a deserted island off the coast of Maine.
While spending the summer in an old house on a desolate Canadian island, Anthony Monday and Miss Eells discover a chest that can transport them to another world and a maniacal group who are plotting the destruction of people on Earth.
Johnny Dixon, Fergie and Professor Childermass comply with a strange will left by the Professor's brother, which requires them to spend the summer at a desolate estate where they encounter a madman bent on destroying the world.
Johnny must find the lost will of Mr. H. Bagwell Glomus, a man of great fortune and sinister witchcraft. mr. Glomus's widow is offering a reward to anyone who finds its hiding place, enough money to help Johnny's grandmother get the operation she needs.
Lewis Barnavelt and Rose Rita Pottinger are faced with a dilemma when their discovery of an unpublished opera score unleashes a wicked sorcerer who plans to rule the world by bringing back the dead.