On 4 April 1962, James Hanratty was led from the condemned cell in Bedford Prison to the gallows. On the way he protested his innocence, as he had done every day since he had been convicted of murder. At 8am, the noose was fitted round Hanratty's neck and he was hanged, launching one of the longest and most bitter appeal campaigns in the history of British justice. Hanratty's supporters believe that he was wrongfully convicted, the victim of dubious police evidence. The police maintain Hanratty was a vicious killer - and say they now have DNA evidence to prove it. After years of doubt, it appears that modern science holds the key to a 40 year old case. It all began when Michael Gregsten drove to the countryside with his lover, Valerie Storie. They had just parked in a quiet lay-by when a gunman got in the back of their car and demanded money. Several hours later Gregsten was dead and Storie had been raped and, with several bullets inside her, left for dead on the side of the A6 road