Arco, Idaho, 1970: the story of three sisters: young Frances, gregarious and strong-willed Jory, and moral-minded Grace. Their father, Oren, is a respected member of the community and science professor at the local college. Yet their mother’s depression and Grace’s religious fervor threaten the seemingly perfect family, whose world is upended when Grace returns from a missionary trip to Mexico and discovers she’s pregnant with - she believes - the child of God. Distraught, Oren sends Jory and Grace to an isolated home at the edge of the town. There, they prepare for the much-awaited arrival of the baby while building a makeshift family that includes an elderly eccentric neighbor and a tattooed social outcast who drives an ice cream truck.