From left, Jessica Chastain, Isabelle Nelisse and Megan Charpentier prove that you don't have to be partying teenagers at a summer camp to run into true horror in 'Mama.'
"Mama" breaks a lot of horror movie rules, right off the proverbial bat.
It gives us a long back-story opening, and brings up much more back story as the tale progresses.
It over-explains. It reveals its supernatural menace, not just in glimpses, but full on, and early on. There's never any doubt that this might be all in somebody's head. ...