In 1886, Gretta Pope wakes up one morning to discover that her husband is gone. Ulysses Pope has left his family behind on the far edge of Minnesota's western prairie, with only the briefest of notes and no explanation for why he left or where he's heading. It doesn't take long for Gretta's young sons, Eli and Danny, to set off after him, leaving Gretta no choice but to search for the boys and their father in hopes of bringing them all home.