Forensic psychologist Paul Britton asks himself four questions when he is faced with a crime scene: what happened: who is the victim: how was it done, and why? Only when he has the answers to these questions can he address the fifth: who is responsible?

An intensely private and unassuming man, Britton has an almost mythic status in the field of crime deduction because of his ability to 'walk through the minds' of those who stalk, abduct, torture, rape and kill other human beings. What he searches for at the scene of a crime are not fingerprints, fibres or blood stains - he looks for the 'mind trace' left behind by those responsible; the psychological characteristics that can help police to identify and understand the nature of the perpetrator.

Over the past dozen years he has been at the centre of more than 100 headline-making investigations, from the murder of Jamie Bulger to the abduction of baby Abbie Humphries, the slaying of Rachel Nickell on Wimbledon Common, the pursuit of the Green Chain rapist and the Heinz baby food extortionist, the notorious Gloucester House of Horror and most recently, the murder of Naomi Smith.

Told with humanity and insight, The Jigsaw Man is Paul Britton's absorbing first-hand account of those cases, and of his groundbreaking analysis and treatment of the criminal mind. It combines the heart-stopping tension of the best detective thriller with his unique and profound understanding of the dark side of the human condition.