'Gangster' Stars On the Effect of Movie Violence

Last summer, Gangster Squad found itself in the middle of controversy when its violent trailer mirrored the tragic events of the audience gunned down in cold blood at an Aurora, CO movie theater during a screening of The Dark Knight Rises. Now, the new movie is finally hitting the big screen with a revised ending, and its stars weigh in on the correlation between film violence and the gun violence so prevalent today.

Video: Gosling & Stone Create 'Gangster Squad' Sparks

"There's so many factors nowadays," Josh Brolin tells ET's Brooke Anderson. "Why wasn't there the amount of violence in society back [in the 1940s] when there was still a massive amount of violence [onscreen]? Is it really because of a movie like Gangster Squad? Is it because of a movie like Saw 9, or whatever the latest Saw is? Is it repression? … Is it because of the fact that parents aren't necessarily at home as much as they were before, and both parents have to work? There's so many different factors. This is an escapist deal when you go to a movie -- you hopefully allow yourself to kind of live [vicariously] through this movie and get that out. … I'm not going to pretend like I know the correlation, but I think it's a lot bigger than movies create incredible and awful violence."

In theaters Friday, the 1940s-era Gangster Squad chronicles ruthless, Brooklyn-born mob king Mickey Cohen's (played by Sean Penn) domination of Los Angeles – and the super-secret crew of LAPD outsiders, including Brolin's character of Sgt. John O'Mara, recruited to stop him.

The controversial scene in the Gangster Squad trailer showed mobsters shooting at an audience inside a movie theater. The trailer ironically ran just before the fateful shooting rampage in Aurora and Warner Bros. immediately pulled it and then ordered reshoots, effectively omitting that climactic scene.

Video: Go Behind the Scenes of 'Gangster Squad'

Of the change to the film's ending, Brolin comments, "I thought it was a smart thing. I really did. I liked that scene a lot, but the correlation was so perfectly paralleled that I think it was respectful to go back. … I actually like the new version better."

Watch the video to see how other Gangster Squad stars feel about the subject, including Emma Stone and Robert Patrick.