In an average year, what percentage of murder gets cleared up by the police? 10 per cent, 40 per cent? Maybe even 70 per cent? Professor David Wilson can reveal the answer - and it might just surprise you. In this four-part series, the Professor of Criminology reveals why everyday who dunnits are poles apart from the sensational crimes that hit the headlines. He explains the myths around killing and uncovers the people who are most likely to be murdered.