The police investigate the murder of Alice Cullin, a young doctor who is found dead in the car park at the hospital where she worked. She was also pregnant. Her fiancé, Joe Nash, works as a porter at the hospital and from all accounts, is a very nice fellow. They find that Joe has been seeing a woman who lives near the hospital and they assume that he was having an affair. The woman turns out to be Daniela Renzo, a psychiatric social worker who is responsible for assisting Joe with his reintegration into society. The police get Joe to confess to the murder but for Crown Prosecutor James Steel, the question quickly becomes just who Nash is when it's revealed he's living under an assumed identity given to him by the Home Office.