Whether or not America is ready for an inquisitive, empathetic film about Christian fundamentalism, it’s got one now from Vera Farmiga, the disarmingly graceful star who here makes her directorial debut. Adapted by Carolyn S. Briggs and Tim Metcalfe from Briggs’ book, This Dark World: A Memoir of Salvation Found and Lost, Farmiga’s film takes an unabashedly personal view of spiritual crisis, limning the challenge posed by critical thinking to one well-behaved woman’s increasingly uncertain faith. The filmmaker, bless her, seems to remain ever-receptive. If the usual easygoing exactitude of her acting is less evident in her direction that may just be a matter of more practice. For a rookie, Farmiga certainly knows the game. Her fine and shrewdly chosen supporting cast includes Dagmara Dominczyk, John Hawkes, Bill Irwin, Joshua Leonard, Donna Murphy and Farmiga’s younger sister Taissa as her character’s younger self.