New York Times bestselling author Margaret Coel explores the nature of evil in this "outstanding entry" (Booklist) in the Wind River Reservation Mystery series.

Father John O'Malley comes across the corpse lying in a ditch beside the highway. When he returns with the police, it is gone. The Arapahos of the Wind River Reservation speak of Ghost Walkers—tormented souls caught between the earth and the spirit world, who are capable of anything.

Then, within days, a young man disappears from the Reservation without a trace. A young woman is found brutally murdered. And as Father John and Arapaho lawyer Vicky Holden investigate these crimes, someone—or something—begins following them.

Together, Vicky and Father John must draw upon ancient Arapaho traditions to stop a killer, explain the inexplicable, and put a ghost to rest . . .