The battle of Britain rages and two young RAF pilots from very different stations in life must somehow find common ground - and stay alive. On the eve of World War II, working-class Eddy Beane is a flight instructor in London. He successfully completes dangerous espionage missions for Air Commodore Keith Park and takes on society-girl June Stephenson as a student. Her ex-fiance, Dudley Thane, is also a flyer, but upper-class and Cambridge-educated. When the German Luftwaffe attacks England in 1940, Eddy and Dudley end up serving in the same Spitfire squadron. Aerial combat is intense, and both men show their skills and courage, but can they set aside jealousy and class differences to become fighting brothers for the defence of Britain?