The coalfields of West Virginia in 1920-1921 were a place of extraordinary labor violence between striking miners facing off against armed mercenaries employed by mining corporations. In the remote mountain valleys of Appalachia, a region made infamous by the Hatfield-McCoy feud, coal miners and their families lived at the margins. Coal mining was a poorly paid brutal and dangerous occupation. Mining companies controlled corrupt local government, exerting a form of institutionalized oppression described as corporate feudalism.

Mine operators refused to negotiate labor agreements. Contracting with the Baldwin-Felts Detective Agency as armed security, mining interests repressed striking miners causing the worst labor violence in U.S. history. Into this hostile environment a decorated former U.S. Marine and an activist female lawyer come to West Virginia and become drawn into the conflict.