'Knock at the Cabin' review: M. Night Shyamalan's latest is for believers

M. Night Shyamalan forged his reputation on enthralling thrillers with mind-blowing twists, like The Sixth Sense, Signs, and Unbreakable. But over the last twenty years, a spotty filmography littered by abysmal offerings (Avatar: The Last Airbender, The Happening, Lady in the Water) has made seeing a Shyamalan movie a gamble in...