The year is 1949 and ruthless gangster Mickey Cohen has the city of Los Angeles in his grip. Against a gang protected by rampant corruption, Police Chief Bill Parker resorts to extremes. He enlists battle-hardened hero Sgt. John O'Mara to form a unit to exact vigilante justice. Their job isn't to make arrests ... it's to make war. As the city explodes in gunfire, jaded cop Sgt. Jerry Wooters is reluctantly drawn into the fight as he falls hard for Grace Faraday, the elegant beauty whom Cohen claims as his own. Inspired by an incredible true story, Gangster Squad blows open the secret files of the cops who fought for LA's soul.