A sadistic killer. A kill list!A retired doctor, brutally mutilated and murdered. Detective Inspector Karen Heath thinks it might be a stranger killing, especially when there are no clues, forensics or witnesses.Who would want to hurt a man in his 60's caring for his wife who suffers from dementia?Karen realises she's dealing with a cold, ruthless killer with a twisted sense of justice, hungry for murder.What started as a difficult and tragic murder investigation, turns into a race against time as Karen finds herself in York looking for answers.Paired with an intriguing and complex DCI Zac Walker, the duo piece together their cases and soon realise they're after the same killer.Can Karen and Zac crack the case before everyone on the list is dead?