MUST-SEE TRAILER: "GANGSTER SQUAD" (TRAILER 2:23)
Sean Penn is the gangster, and Josh Brolin and Ryan Gosling are out to stop him in 1940s L.A.

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"Gangster Squad"
Courtesy Warner Bros. Pictures

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Trailer featuring Sean Penn, Josh Brolin, Ryan Gosling, Emma Stone, Giovanni Ribisi and Nick Nolte

--LEAD-IN SCRIPT--

When East Coast mobsters hit Los Angeles in the 1940s, L-A hit back!

Here's a look at the star-studded action thriller "Gangster Squad," opening in September.