In the dying days of the old west, an elderly sheriff and his posse set out to rescue their town's doctor from cannibalistic cave dwellers.

After an outlaw unknowingly leads a band of cannibalistic Troglodytes into the peaceful western town of Bright Hope, the monsters kidnap several settlers, including the wife of a local rancher.

Despite his injured leg the rancher joins a small rescue party with the sheriff, his aging deputy and a strong-willed gunslinger. What follows is a journey into hell on earth as the posse comes to realize it is up against a foe whose savagery knows no bounds. The film takes place in the mid 1800's around the border of what is now Texas and New Mexico.