Fifteen-Year-Old Christopher has a Photographic Memory. He Understands Maths. He Understands Science. What he can"t Understand are other Human Beings. When he Finds his Neighbour"s Dog, Wellington, Lying Dead on the Lawn, he Decides to Track down the Killer and Write a Murder Mystery About it. But in Doing so, he Uncovers other Mysteries that Threaten to Bring his Whole World Crashing down Around him.