Ambitious, intellectual and deeply humanistic, Ava DuVernay’s “Origin” opens with a soul-shattering prologue. A Black teen runs an evening errand at a white neighborhood in Florida. He is on the phone with his girlfriend, complaining about a suspicious guy following him in his car. Both are concerned and his girlfriend asks him to let her know when he’s back home. We don’t see the end of the episode, because we don’t have to. The Black teen’s name is Trayvon Martin, fatally shot on a February night in 2012 by George Zimmerman, a man of Hispanic descent, for no reason.

It’s a disquieting sequence of shadows, reflections and a sense of claustrophobia, shot with remarkable skill as well as a sense of duty and restraint. While complimenting the quality of filmmaking behind a devastating moment of recent American history might be a tad crass to some eyes and ears,...