Tom's life is not what it once was. His marriage to the beautiful Nora is on the rocks and he now sees his two young children only on her say so. His best friend - and best man - Neil has moved away to California to teach neurology and he barely sees him. He has one successful book - on human psychology - but he now wiles away the time trying to teach bored grad students things that they are often not equipped to understand. But that all changes when Neil comes back into his life. For it seems that his best friend was no teacher - he was working for the US government, cracking the minds of suspected terrorists. But now it is Neil himself that has cracked and gone AWOL - what's more he has left behind evidence that he has been employing his unique skills on civilians - obsessed with the idea that he can control the human brain. Thus begins a terrifying sequence of events as Neil starts to kidnap and mutilate people with a connection to Tom. He damages their brains selectively and then releases them - often leaving them mad. But it is only when he gets near his ultimate target does he reveal the full horror of his plan...