Three Civil War veterans team up with a train robber's widow to recover the loot from her husband's last job--a cool half-million in gold which is hidden somewhere south of the Mexican border. For backup they've got two nervous young gunslingers and a balky mule packing enough dynamite to blow up the Alamo.

A band of robbers are running from the law, and they find an almost abandoned town. An old prosecutor and his granddaughter have been living there. Realizing that they have gold, the robbers have a plan of taking it, but one robber turns against them.