Soviet Scientist Petrovich pioneers the way to the Sun, but his spacecraft is never heard from again. Later, Andrew's laboratory investigates means of protection from deadly radiation. Andrew repeats Petrovich's journey, and offers his life to rescue an orbiting science laboratory, which holds the solution to the problem.

A certain number of French fighter pilots who will not accept the Second Armistice at Compiègne nor Vichy's orders decide to join the USSR. Once they have reached Moscow they resume training and form a squadron they call "Normandie". Reinforced in 1944, the squadron wins many victories. Following the acts of valor displayed by its pilots during the Battle of the Nieman River, it becomes the "Normandie-Niemen" squadron for the rest of times...