The Secret Witness - Victor Methos

From the bestselling author of A Killer's Wife comes the thrilling first installment in the Shepard & Gray series, featuring a young sheriff who teams up with a former prosecutor to stop a copycat killer. This is Reaper speaking.
So begins an anonymous letter published in a Utah newspaper after a young couple is viciously murdered. Tooele County sheriff Elizabeth Gray leads the investigation into the double homicide, which is eerily reminiscent of a string of brutal killings years ago. When the letter leads detectives to yet another body, Gray calls on an old friend for help.
Former prosecutor Solomon Shepard is still struggling to recover from the deadly courtroom attack that ended his career. He's been keeping a safe distance from the action, teaching criminology seminars about serial murders and psychopathology-until Gray asks for his help on the Reaper case.
As the body count mounts, Shepard and Gray race to unravel the deranged design of a copycat killer-and find themselves in a face-off with an enemy they never saw coming.