Saddle tramps BEAU NICKLE and VIRGIL DIME (pronounced Dee-may') are bound to try their luck in the California Gold Rush, partly as a change of scenery, partly due to Val having crossed Confederate officer MAJOR BELLOCQ over the affections of a soiled dove back in New Orleans.
Beau and Virgil find themselves caught in a deadly winter storm in the Sierra Nevada mountains, freezing to death. They find shelter in an isolated cabin where they come upon LUCINDA BELL, daughter of a miner recently lost in a tragic mine cave-in. As the threesome make the dangerous trek to reach Fort Calqhoun, they reach the cabin of JACK McCREADY, one of the miners also lost in the cave-in. Inside, they discover the miner's WIFE and DAUGHTERS brutally slaughtered and are attacked by Jack McCready who appears to have returned from the dead.... and gone mad. They "kill" McCready only to discover undead are roaming the snowy landscape and on their trail.
The threesome battle their way to Fort Calqhoun, only to discover the survivors of the mining camp and town held captive by a crazed, one-legged CORPORAL O'ROURKE in command, determined to defend against "Confederate saboteurs" no matter how many living and undead he has to kill.
WA'ETSE, an old Paiute warrior trained to battle the undead, appears with his daughter, ESA. He claims that an ancient evil is resurrecting the dead and must be destroyed before the Spring arrives and settlers pass through on their way west.
With Bellocq and his men hot on their trail, O'Rourke and his soldiers summarily executing anyone who disobeys his commands, and the undead clawing at the fort's gates, Beau and Virgil must find the source of the undead and destroy it or face the spread of ancient evil into the American West.