Chaim Bruk, a charismatic 34-year-old Hasidic Chabad-Lubavitch rabbi from Brooklyn, brings his evangelical strand of Judaism to Bozeman, Montana, with the mission to place a mezuzah (encased Jewish prayer offering) on the doorpost of every Montana Jew. As he travels across this “big sky” landscape, Chaim faces obstacles, including a terrifying neo-Nazi threat and objections from some skeptical Jews and the state’s Reform and Conservative rabbis. Will Chaim succeed in his Chabad expansion, and at what cost?