The unscrupulous attempts by speculators Dr. West and Jim Prince to have a railroad pass through lower California are met with opposition by Spanish landowners led by Dona Maria Saltonstall, who tries flirting with West to restore their property. Pereo, a religious fanatic who works for Dona Maria, believes in the curse of the Gray Wolf's Ghost: if a member of Dona Maria's family mates with an alien, fortune and life will be lost. Meanwhile, West's son Harry, whom he deserted years before, comes...