Seven is black, white, and R-rated all over. Even though John Doe doesn't kill his victims onscreen, Hostel-style, the crime scenes are some of the most gruesome ever.
Or, at least they were until CSI started airing on primetime television.
Whether you're desensitized to gore or not, the crimes are brutal in nature. A man is fed until he bursts. Someone is starved over the course of a year. And a prostitute is murdered with a weapon so heinous that BBC One wouldn't even show the tool that did it.
On top of all of this, the cops don't walk around saying "golly-gee!" at the carnage. They drop f-bombs 74 freaking times. Seven is age-appropriate for pretty much no one.