Clash of the Demons by Joseph Delaney
I finished Clash of the Demons last night. Kids are always asking for scary books, and this series is pretty scary! Here is a synopsis from the card catalog: "Tom is reunited with his mother and must return to Greece to face a new and terrible threat from the dark forces, and a momentous decision must be made, causing a serious rift between Tom and the Spook that threatens to separate them forever."