After the fall of Tobruk in June 1942, U.S. Army sergeant Joe Gunn leads his tank into the Sahara desert, in order to evade advancing Rommel's forces and reach Allied lines. Along the way he picks up few Allied soldiers, but soon they are running out of water. They find water at the ancient well, but the well is a goal of an entire German battalion. Despite the impossible odds, Sergeant Gunn decides to defend the well.