The Late Show by Michael Connelly

LAPD detective Renee Ballard has been relegated to the late shift after accusing a superior of sexual harassment. Working 11pm-7am, Renee always has to pass the cases she and her partner work on to other detectives, which is frustrating. When an opportunity arises to investigate an assault that left the victim near death, she decides to work on it off-hours. Renee is also peripherally involved in the investigation of a club shooting that left five dead. Soon enough, Renee realizes that working "the late show" might give her the challenge she's looking for.