When the murdered body of a woman is found in a Sheffield carpark former cop turned private investigator Matt Forrester finds himself embroiled in the case because the last call the victim made was to him. . . But the case isn't as simple as the drug theft it looks like and - when a young boy becomes the next victim - Matt and his life partner DI Karen Nelson realise they're investigating a terrifying series of revenge killings. Arrests start to be made but enemies are being made. And as the killings continue nobody is safe. . .