Zero stars. Why does everyone on here give this terrible movie so much praise? We can watch the nightly news to see stories of people being murdered every day. We don't need to go into the mind of a killer to find entertainment.
Filmmakers have to keep upping the ante all the time to make their movie more shocking than the last. Keep feeding the public a sickening, unending diet of guns and violence. I guess that's what our society wants.