So many films about real acts of human evil feel so watered-down and tentative toward their subject matter. Not Steve McQueen's "12 Years a Slave," which, one year after Quentin Tarantino's slavery film ("Django Unchained") that bordered on comedy and a month before the inexcusably cute Holocaust film "The Book Thief," sets the bar for truth and horror and chance. Based on the novel by Solomon Northup (Chiwetel Ejiofor), a free man who in 1841 New York was kidnapped and sold into slavery, the film features many extraordinary performances, particularly from Ejiofor and Michael Fassbender as a slave owner who is that much more terrifying because he's always believable. Seeking only to depict the way things were and challenge us to watch and discuss, McQueen treats the act of holding a mortgage on a person as the abomination it is. There may never be a better film made about slavery in America.