The Calling of the Grave — Simon Beckett

A forensic pathologist must once again confront a twisted serial killer in the international bestselling author's “bone-chillingly bleak” crime thriller (Financial Times).
 
When Det. Insp. Terry Connor turns up on David Hunter's doorstep, it's an unwelcome reminder of the past in more ways than one. They had once worked together, recovering the victims of a serial killer on the bleak expanse of Dartmoor in Southern England. When Terry's behavior caused a bitter rift, the partnership ended. But now the serial killer -- a psychotic rapist and murderer named Jerome Monk -- has escaped from high-security prison. And he seems to be targeting anyone involved with the search. 
 
David has no choice but to return to his past that is far from dead and buried -- especially when he receives a mysterious appeal for help from Sophie Keller, who also worked with the recovery team in Dartmoor. As he is drawn back into Jerome's twisted world, David discovers that nothing about the original case was what it seemed. And as the maniac's bloody trail edges ever closer, David is forced to question who he can really trust.