In 1924, an orphan train passes through the Midwest, and two teenagers, seeking a new life, find nothing but hardship when taken in to live on a farm in Michigan. Mercy, a teenage girl of mixed race, and a boy nicknamed Rope, who lost fingers in a factory accident, become virtual prisoners of Harlan and Estelle Nau, whose children died during the Spanish flu epidemic. After facing abuse, Mercy and Rope flee, making an arduous journey into sparsely populated northern Michigan, where Mercy believes she will find her aunt. After Harlan is found murdered on his farm, police captain Jim Kincaid pursues Mercy and Rope to the cold, barren villages on the Mackinac Straits, but his efforts are complicated by the reemergent Ku Klux Klan, which has formed a coalition with the police deputy Milt Waters and the Dingley brothers, who run a local bootleg operation. Resolute and intrepid, Mercy and Rope develop a bond of mutual trust that helps them navigate a stark American landscape shaped by prejudice, hypocrisy, and fear.