Hell on Wheels centers on the population of the town that follows the construction of the Union Pacific Railroad. Characters include those directly employed by the railroad and the town’s people themselves, most of whom travel with the roving town.

Cullen Bohannon is the central character driving the show. His main support comes from his right-hand man, Elam Ferguson, and the financier of the railroad, Thomas Durant. The main protagonist is that of Thor Gundersen (AKA “The Swede”), who initially serves as the corrupt security chief and right-hand servant of Thomas Durant. Later, the character is established as a true villain who seeks out revenge on Bohannon and the other inhabitants of Hell on Wheels.