After twenty-five years as sheriff of Absaroka County, Walt Longmire's hopes of finishing out his tenure in peace are dashed when Cody Pritchard is found dead near the Northern Cheyenne Reservation. Two years earlier, Cody has been one of four high school boys given suspended sentences for raping a local Cheyenne girl. Somebody, it would seem, is seeking vengeance, and Longmire might be the only thing standing between the three remaining boys and...

It's homecoming in Absaroka County, Wyoming, but the festivities are interrupted when a homeless boy wanders into town. A Mormon "lost boy," Cord Lynear is searching for his missing mother. Sheriff Longmire and companions Victoria Moretti and Henry Standing Bear embark on a high plains scavenger hunt to reunite mother and son. The trail leads to an interstate polygamy group that's harboring a stockpile of weapons and a vicious vendetta.