The detective, and narrator Christopher Boone is fifteen and has Asperger's, a form of autism He knows a very great deal about maths and very little about human beings He loves lists, patterns and the truth He hates the colours yellow and brown and being touched He has never gone further than the end of the road on his own, but when he finds a neighbour's dog murdered he sets out on a terrifying journey which will turn his whole world upside down