讲述了WWII二战期间，在北美招募的大批民间飞行员为英国皇家空军秘密的从加拿大通过寒冷的北冰洋运送战争所急需的飞机的历史。直到美国对日宣战，这些民间飞行员才被编入RAF英国皇家空军，继续为二战同盟国执行运输飞机到战场前线的任务。其中包括有一次极为成功的绝密任务，把丘吉尔运送到埃及慰问北非作战的英国远征军，并转道去几乎被德军围困的莫斯科与斯大林面谈并将丘吉尔安全送返英国的传奇任务。 直到战争结束，RAF运输队共为皇家空军运送了超过1万架各型飞机，有500名飞行员因气候及故障而丧命。 Flying the Secret Sky tells a story of passionate risk-taking, of young men braving dangerous flights in primitive aircraft. These "cowboys of the air" are forgotten heroes of the war, who flew without guns and embodied an improvisational spirit that was key to Allied victory. Their story includes the American civilian chosen to fly Winston Churchill to secret wartime meetings during the darkest days of WW II. A story the world never knew, until now.