Gangster Squad

This movie is apparently based on real events and there is also a lot of historical liberties included in the screenplay.

It begins in the late 40s with Mickey Cohen (Sean Penn), a mobster who has become quite powerful and has made of Los Angeles his base of operations. Cohen's power is at his peak since almost everyone who can be bought is already in his payroll.

One member of the police, John O´Mara (Josh Brolin) believes in what is right and despises Cohen. One day, O'Mara receives from one of his superiors one order that is his dream come true. Chief Parker (Nick Nolte) asks O'Mara to start a secret squad to stop Cohen`s operations and therefore free Los Angeles from all the criminal activity that had alreayd taken over other cities at the time. This secret group, of which there is no historical record, included Segeant Jerry Wooters (Ryan Gosling), Officer Kennard (Robert Patrick), Officer Ramírez (Michael Peña) among others. It is thanks to this squad that Los Angeles got free from the criminal influence that was threatening to tarnish L.A. forever. 

This movie contains a lot of violence, but also great prformances and a soundtrack that combines perfectly with the action in every scene. In particular, Penn as Cohen is astounding giving his role the necessary qualities it requires. His impersonation of that gangster would  have  been memorable had he had more screening time.
Ganster Squad is in the end a movie that fits perfectly in the genre of  Action and Crime movies and would be a jewel for the followers of the genre.
Four stars out of five stars.