What is the last line of The Curious Incident of the Dog in the Night-time?

It depends which publication you get. My copy (VINTAGE books, 2004) reads:

The Curious Incident of the Dog in the Night-Time is a murder mystery novel like no other. The detective, and narrator, is Christopher Boone. Christopher is fifteen and has Asperger's Syndrome. 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 of a terrifying journey which will turn his whole world upside down.