The Volga River is the heart of the Russian People and the last line of defense against the German invasion. The Russian Army is fighting desperately to defend against the German onslaught and to hold the last bridgeheads on the west bank of the Volga. But, help is coming. American personnel, supplies and equipment are pouring into Russia and at the head of the flood are the B-17 Flying Fortresses and P-47 Thunderbolts. Together the heavy bombers and their fighter escorts strike at targets deep in the heart of German-occupied Russia. As the great air battles take place, the Luftwaffe pilots realize that their days of air superiority and easy victories are over and they now face a fight just to survive. Meanwhile, as Russians and Americans fight side by side, what began as an uneasy alliance matures into a firm friendship.