The official trailer for 'The Gangster Squad' starring Sean Penn, Ryan Gosling, Emma Stone and Josh Brolin. 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 wire bet placed west of Chicago. And he does it all with the protection of not only his own paid goons, but also the police and the politicians who are under his control. The small, secret crew of LAPD outsiders led by Sgt. John O'Mara (Josh Brolin) and Jerry Wooters (Ryan Gosling), come together to try to tear Cohen's world apart. "Gangster Squad" is a colorful retelling of events surrounding the LAPD's efforts to take back their nascent city from one of the most dangerous mafia bosses of all time For all the latest movie and entertainment news check out Deadline.com www.deadline.com