A small-town cop and his big-city ex-partner--who happens to be a robot--try to solve a murder that seems to lead to a mysterious drug-trafficking network in Ariel S. Winter's The Preserve.
Winter writes a real genre-buster; it is a hard-nosed buddy-cop crime novel, but in a dystopian future where the human race has been reduced by plague (!) and has ceded control to robot overlords. What few humans remain live in a vast self-governed preserve that functions somewhat like a reservation, with the robot government always sniffing around the borders.
What I liked about it was that the world-building is in the far background; the mystery is grounded in two cops chasing bad guys over 24 hours, with the clock ticking on a dangerous drug getting out. There's no planet-shattering change in the status quo by the end of the fast-paced story.
Highly enjoyable and offbeat police procedural/science fiction mashup.
I checked this out from the New Castle-Henry County Public Library and read it quickly.