Barnaby Grimes: Return of the Emerald Skull

Return of the Emerald Skull, by Paul Stewart and Chris Riddell, is 203 pages long and is about a boy named Barnaby Grimes. He is a "Highstacking Tick-Tock Lad" and is suppost to deliver fragile stuffed birds to the Headmaster of a school. It turns out that the school is being haunted by an evil skull made of Emerald. As the hipnotised school-children are trying to kill him on the orders of the Emerald Skull, Barnaby must distroy the skull or let its victims distroy him.