Salty and the Serpent by Robert Saltzman.
Bobby Salter is a cop's cop.A basic patrol officer, Bobby and his partner Vinny Serpentino have just brought down the empire of two of the biggest coke dealers in Brooklyn. With a huge money bust in their back pocket, they are promoted to plain clothes officers and assigned to patrol the streets of Bobby's grandfather's old neighborhood. 
As his resume begins to build, Bobby's rise takes him all the way to detective as he's thrust into solving high profile cases from Manhattan to the Bronx. As the action twists and turns, Bobby's story will lead to a surprise ending that no one would ever see coming.
A deep look into the world of policing, this fantastic crime thriller peels back the rose-colored surface of society to reveal the seething underbelly that lies beneath
A very good read with good characters. Bobby was my favourite. Good story and characters. 4*.