The Book of Souls

Each year for ten years, a young woman's body was found in Edinburgh at Christmastime: naked, throat slit, body washed clean. The final victim, Kirsty Summers, was Detective Constable Tony McLean's fiancée. But the Christmas Killer made a mistake, and McLean put an end to the brutal killing spree.
It's now twelve years later. A fellow prisoner has just murdered the incarcerated Christmas Killer. But with the arrival of the festive season comes a body. A young woman: naked, washed, her throat cut.
Is this a copycat killer? Was the wrong man behind bars all this time? Or is there a more frightening explanation?
McLean must revisit the most disturbing case of his life and discover what he missed before the killer strikes again . . .