When Agatha Christie, the so-called 'Queen of Crime', disappeared from her home in Sunningdale in Berkshire for eleven days on 3 December 1927, the whole nation held its breath. The following day, when her car was found abandoned fourteen miles away, a nationwide search was instigated. From a painstaking reconstruction of Agatha's movements and behaviour during those eleven days, Dr Andrew Norman is able to shed new light on what, in many ways, has remained a baffling mystery. Only now, fifty years after Agatha's death, is it possible to explain fully, in the light of scientific knowledge, her behaviour during that troubled time.