High Country Nocturne (David Mapstone Mysteries)

"A cache of diamonds is stolen in Phoenix. The prime suspect is former Maricopa County sheriff Mike Peralta, now a private investigator. Disappearing into Arizona's mountainous high country, Peralta leaves his business partner and longtime friend David Mapstone with a stark choice: he can cooperate with the FBI, or strike out on his own to find Peralta and what really happened."--