Having successfully completed a Congo campaign, mercenary Mark Anderson undertakes a Brazilian assignment. Hired by entrepreneur Manuel de Lagos, Anderson circumvents saboteurs intent on possession of the capitalist's mines, famed for their ores used in the production of nuclear weapons. Through an intermediary, a former African colleague, Anderson negotiates an arms shipment from the saboteurs. When an innocent child and de Lagos are murdered, the mine owner's seductive widow, Isabel, entreats the mercenary to capitulate. Instead, Anderson arms the miners, who successfully repel the saboteurs and appropriate the mine.