Season Four of “Hell On Wheels” finds civilization making its way west with the railroad, bringing with it men who attempt to do with their pens what rougher men did in seasons past with their guns. Conflict between government and big business, ranchers, homesteaders and the railroad will continue to define the drama as all of those interests compete with one another for control of Cheyenne, Wyoming, the “Magic City of the Plains,” and the most important railroad hub in the country.