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...

Soviet spy Ladeynikov learns that in one of the pharmaceutical centers in a small resort town works a former German war criminal, Dr. Hass, who is finishing the creation of a deadly chemical gas RH development that he began during World War II, experimenting on POWs. Since Ladeynikov doesn't know Dr. Hass's appearance, Soviet intelligence recruits an actor, Ivan Savushkin, who, during the war, escaped from a prison camp where Hass was testing his gas. Together, they must identify and stop him before he finishes and unleashes his weapon of mass destruction.

Danka's and Ksanka's childhood in the village brutally ends when their father is killed by a White Guard officer in front of their eyes. Seeking revenge, they join forces with Valerka, an intellectual from big city, and the gipsy Yashka, but before they can get close to their enemy they have to help their village and the advancing Red Army.