Based on the true story of Russian pilot Valeri Chkalov (1904 - 1938), who set several long-distance flight records. Chkalov and co-pilots Baidukov and Belyakov altogether had accomplished several nonstop long-distance flights. In June 1937, Chkalov set the world record, covering 12,000 kilometers in 63 hours of nonstop flight from Moscow to Vancouver, Washington, flying over the North Pole.