I've seen it. Just my opinion, I wouldn't bring a child to it. The violence is graphic but mainly I wouldn't because of a pretty horrific rape scene. Also, violence against women is a huge part of the plot line.
All of this said, I liked the movie, but I come from it from the perspective of a Swedish person who has the read all the books and is familiar with Stieg Larsson's work and philosophy (he was actually a feminist).
But if I didn't have that context, I would not have seen the movie. I probably would have found it overly dark and disturbing.
My 0.02$ :)
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