Red River Valley, 1869. Hoardes of ex-Confederate soldiers have emerged from the piney hills and mosquito-infested swamps of Louisiana backcountry in a final, bloody show of defiance. After a series of violent raids on carpetbaggers, freed slaves, and Northern cargo ships, Captain Douglas Owens of the 4th Calvary is given orders to reclaim this godforsaken land from its murderous outlaw gangs.
In the high Rocky Mountains, Civil War veteran Marshall Brewster has a vision of wealth and fame. Under the tutelage of a hardened railroad tycoon, Brewster will build a railroad connecting Colorado's booming silver mines to a country starved for wealth - and maybe win himself the hand of a beautiful woman in the process. But as in war, Brewster's plan is soon shattered by the enemy.