In this old-fashioned jungle adventure, a British engineer, Colonel John Patterson is sent to the Tsavo River deep in the East African wilds to construct a vast railroad bridge as part of the Pan Africa railway. But instead of focusing all his attention on getting his crew, comprised of a tempestuous crowd of natives, Moslems and Hindus, to construct the bridge, he ends up fighting a nearly mystical pair of man-slaughtering rogue lions with the help of an Africanized great white hunter. The film contains considerable violence as the lions turn out to be voracious and ruthless killers. The plot is allegedly based upon a true story.