Los Angeles, 1949. Ruthless, Brooklyn-born mob king Mickey Cohen (Sean Penn) runs the show in this town, reaping the ill-gotten gains from the drugs, the guns, the prostitutes and—if he has his way—every bet placed west of Chicago. He not only does it all with the protection his paid goons, but also the police and the politicians who are under his control and supposed to protect the general public. It’s enough to intimidate even the bravest, street-hardened cop…except, perhaps, for the small, secret crew of LAPD outsiders led by Sgt. John O’Mara (Josh Brolin) and Jerry Wooters (Ryan Gosling), who come together to try to bring Cohen down.