In 1990, James Ellroy wrote a crime drama called L.A. Confidential set in the 1950s. I've never read the book, although perhaps I should. Director Curtis Hanson co-wrote the screenplay, and the film was released in 1997. His first step in making the movie was an incredible attention to detail in people's dress, the sets, the cars, everything. This is a good place to start. But it's not what the movie's about, it's just a part of the foundation: on top of this he got a fantastic ensemble cast (Guy Pearce, Kevin Spacey, Russell Crowe, Kim Basinger, David Strathairn, James Cromwell) to do a great performance of a dark and complex story of corruption and murder.
Pearce is Ed Exley, a straight-laced (and very intelligent) cop who chooses to start his career by informing on fellow officers. Crowe is Bud White, a thuggish enforcer who eventually starts using the brain he's been gifted with, and Spacey is Jack Vincennes, a cop who spends most of his time consulting on a TV cop show and taking pay-offs for busts to go on the cover of a local sleaze tabloid. A series of events brings the three together on a collision course as organized crime in the city gets a vicious re-organization by parties unknown.
The movie has withstood multiple viewings, and I watch every moment of it avidly every time because it's ... well, perfect. A movie that expects you to pay attention, it moves fast, it's shocking, and you really aren't going to see the twists coming. Pay attention - and enjoy.