The Murder Wall by Mari Hannah
Eleven months after discovering a brutal double murder in a sleepy Northumbrian town, Detective Chief Inspector Kate Daniels is still haunted by her failure to solve the case. Then the brutal killing of a man on Newcastle's Quayside gives Daniels another chance to get it right, and her first case as Senior Investigating Officer. When Daniels recognises the corpse, but fails to disclose the fact, her personal life swerves dangerously into her professional life. But much worse, she is now being watched. As Daniels steps closer to finding a killer, a killer is only a breath away from claiming his next victim...