With the Civil War over, ex-Confederate soldier Cullen Bohannon (Anson Mount) journeys west to avenge his wife's death and finds work in the lawless town of Hell On Wheels, where the transcontinental railroad is staging its cross-country expansion. Once there, he crosses paths with an emancipated slave (Common), a greedy entrepreneur (Colm Meaney), and a freshly widowed woman (Dominique McElligott).