In the prewar days leading up to the Second Sino-Japanese War of 1937, head flight instructor Lt. Katō Tateo of the Imperial Japanese Army-Air Corps trains new volunteers from the Army's Infantry to become Japan's next generation of fighter pilots at the Tokorozawa Flying School. Flying Kawasaki Ko-4 biplanes, Lt. Katō will train both friend and future foe alike. But as war in China breaks out, Katō now in command of the 5th Rentai will take his untested men flying antiquated planes into aerial combat against the Chinese Air Force who is now headed by Lt. Cho who Katō both earlier befriended and personally trained himself. While Katō's squadron ultimately achieves air superiority over the skies of Manchuria, it comes at a high price in men to which each loss carries a heavy burden that he alone must carry. As the war widens into the Second World War, Captain Katō must battle an ever advancing array of deadlier new enemies flying ever more modern fighter planes.