A Memphis DJ hires recent World War II veteran Bull Ingram to find Ramblin' John Hastur, a mysterious bluesman whose dark, driving music — broadcast at ever-shifting frequencies by a phantom radio station — is said to make living men insane and dead men rise.

A bootlegged snippet of Hastur's strange, brooding tune fills Bull with an inexplicably murderous rage. Driven to find the song's mysterious singer, Bull hears rumors that the bluesman sold his soul to the Devil. But as Bull follows Hastur's trail into the eerie backwoods of Arkansas, he'll learn there are forces much more malevolent than the Devil and reckonings more painful than Hell . . .