Christopher, a fifteen year old boy finds his neighbor's dog Wellington dead during the night time.
Christopher finds out his father Ed Boone was the perosn who killed the neighbor's dog because of argument he had with the neighbor's wife.
Christopher finds hidden letters from his mother who his dad suspected was dead.
After his dad told him he killed wellington and lied about his mothers death,he didn't trust him and was scared of him. So he thought he'd run away from home and travel to London to find is mom now that he was scared of his father.
Christopher finds his mom with her secret loved one , Mr. Shears, the owner of Wellington.
At the end, Christopher gets a new dog, a golden retriever and pursues his goals.