According to Sci-Fi Wire Robert Rodriguez, who co-directed the upcoming comic-inspired Sin City, defended the film's violence in comments to reporters over the weekend. I dont see why he has to. The books are extremely violent and so is his movie. The movie is not for kids and Robert says as much(read on).
"It is so over the top and stylized, like in the book, that's what helped temper it," Rodriguez said in a news conference. "It was so black and white, so abstract, so representative, that it's ... easier to watch, I think, than if ... it was realistically rendered. It's the tone of it, I think, that really changes it."
But Rodriguez agreed that Sin City isn't for children.
"Young people shouldn't see it," he said. "It's a rated R movie. ... I'm not making it for that [family] audience. ... I made this an R. I didn't try and trick people into making it a PG-13. ... If parents let their kids in, that's their decision. But that doesn't mean that I'm going to change how we're going to make the movie. Frank made his thing in a vacuum, ... and I wanted to do the exact same thing for cinema and suffer the consequences. If people don't go see it because it's R, that's fine. It's not appealing to the mass audience. It's really just about making the movie we want to make and telling the story that we want to do. "
Be sure and read Hakeems Sin City Movie Review