Having been the victim of a hit and run accident, and despite being black and blue, DI Munro wastes no time in trying to find out the identity of the perpetrator. In the meantime, a junior detective receives a call from a concerned member of the public, worried that a recently deceased friend's will had been unlawfully changed. What connects these two events will be crucial to the detective's investigation. But when prime witnesses turn up dead, they'll discover they have a more serious case on their hands. With attempted murder upgraded to a full-scale murder investigation, can the police close in on a mysterious killer or will Munro be finally outwitted?