Declaring he needs to clear his conscience, a dying man walks into Scotland Yard and confesses that he killed his cousin five years earlier during the Great War. When Inspector Ian Rutledge presses for details, the man reveals little else, only that he hails from a village somewhere east of London. With scant information to go on and no corpse, Rutledge cannot launch an official inquiry, but he is intrigued enough to look into the case on his own. Everything changes when the body of the confessed killer is found floating in the Thames, a bullet in the back of his head, and Rutledge discovers that the guilt-stricken alleged murderer was not who he claimed to be.
With but one clue to go on, a gold locket found around the dead man's neck, Rutledge finds himself drawn to an insular village in Essex, where the residents will do anything to keep out of the public eye. For notoriety could bring attention to a centuries-old act of evil that, even now, could damn them all.