Nightshade - Michael Connelly

Los Angeles County Sheriff's Detective Stilwell has been "exiled" to a low-key post policing rustic Catalina Island, after department politics drove him off a homicide desk on the mainland.

But while following up the usual drunk-and-disorderlies and petty thefts that come with his new territory, Detective Stilwell gets a report of a body found wrapped in plastic and weighed down at the bottom of the harbor. Crossing all lines of protocol and jurisdiction, he starts doggedly working the case.

Soon, his investigation uncovers closely guarded secrets and a dark heart to the serene island that was meant to be his escape from the evils of the big city.