I can't rate 12 Years a Slave, I cannot be objective about it technically. It was so disturbing to watch that I considered leaving many times, after each unspeakable act of violence and man's inhumanity to man, and that was most of the film.
The story opens with Solomon's life as a free man in New York - his idyllic home and family (which didn't seem historically correct to me, but maybe was intended, to contrast with what happens next) and then the excruciating horror begins when Solomon is kidnapped and wakes up in chains. The cruelty and violence never let up. Not for a second.
The film runs two hours and fifteen minutes, and two hours of it made me cringe, look away, brought tears to my eyes. It's unbearably sad. This period in our history is beyond comprehension.
Do I recommend that you see it? Yes, but be warned: It's not easy. Like the holocaust it's part of our history that can't be ignored. Pretending it didn't happen won't make it go away.