James Ellroy, L.A. Confidential, 1990

The story follows several Los Angeles Police Department officers in the early 1950s who become embroiled in a mix of sex, corruption, and murder following a massacre at the Nite Owl coffee shop. The story eventually encompasses organized crime, political corruption, heroin trafficking, pornography, prostitution, and Hollywood. The title refers to the scandal magazine Confidential, which is fictionalized as Hush-Hush. [Source]
 

L.A. Confidential is epic "noir", a crime novel of astonishing detail and scope written by the bestselling author of The Black Dahlia. A horrific mass murder invades the lives of victims and victimizers on both sides of the law. And three lawmen are caught in a deadly spiral, a nightmare that tests loyalty and courage, and offers no mercy, grants no survivors. [Source]

James Ellroy