Gangster Squad is Ruben Fleischer's third feature film, after Zombieland(2009) and 30 Minutes or Less (2011), and follows Mickey Cohen(Sean Penn) a ruthless mobster who wishes to rule the whole of LA and will stop at nothing to get what he wants. Then Chief Parker(Nick Nolte) assigns Sgt. John 'O Mara(Josh Brolin) an off-the-books mission where he must recruit members to tackle and take down Cohen's plan.