Based on the true story of the first female-only aviation regiment in the Soviet Union, 'Sisters in the Sky' follows Nina and her best friend Katya as they decide to volunteer for the first female-only aviation regiment, led by the legendary pilot Marina Raskova. But fighting a war is nothing like they expected, and soon the battle lines are no longer restricted to the front - a forbidden love begins to blossom, and Nina is faced with the ultimate betrayal. Will Nina and her loved ones make it out alive?