"Dark Sacred Night" (Little, Brown and Co.), by Michael Connelly
Los Angeles Police Department detective Renee Ballard was introduced in Michael Connelly's popular "The Late Show." She was given the graveyard shift after reporting her former partner for harassment, and she doesn't let the poor assignment distract her from her duty.
One late evening she sees someone going through old file cabinets and confronts him. He tells her his name is Harry Bosch and he's working on a particular cold case he wants to solve involving the murder of a 15-year-old runaway. Even though he's retired from the LAPD, he's working for the San Fernando police department as a reserve officer tackling unsolved crimes. After Bosch tells Ballard the details, she informs Bosch that he needs to leave since they could both get into trouble. After he leaves, she realizes her curiosity has been piqued and now she wants to uncover the girl's killer as well.
Ballard offers to assist in the investigation and even helps take off hours to go through old notes written by the officers who originally tried to solve the murder. She and Bosch soon become hesitant partners. They will have to work together to build trust, but obstacles in both the cold case and current investigations will quickly put their relationship to the test.
Readers know that when they pick up a Michael Connelly novel they will get a compelling and well-written dive into the world of crime and law enforcement. The cases that Ballard and Bosch tackle would be enough to recommend this story, but what makes Connelly so much better than most crime fiction writers is that his police detectives are human and real. The combination is quality.