The Nazis, exasperated at the number of escapes from their prison camps by a relatively small number of Allied prisoners, relocate them to a high-security 'escape-proof' camp to sit out the remainder of the war. Undaunted, the prisoners plan one of the most ambitious escape attempts of World War II. Based on a true story.

Sommeren og høsten 1940 markerte innledningen til nazistenes planlagte invasjon av Storbritannia. Slaget foregikk i luften og ble avgjørende for krigens videre forløp. Britenes luftforsvar ble ledet av lord Downing, som i denne filmen blir spilt av Laurence Olivier.

Canadian Mountie Steve Wagner captures a German Luftwaffe officer on a spy mission, who later escapes from the prison camp. To catch the spy ring, the Mounties employ a ruse so that the spies, believing Steve to be sympathetic, enlist him in their plans.

A young pilot, fresh out of training, is called to join a Flight while they wait for the call to scramble. Throughout a single day, he witnesses the skies of southern England filled with deadly dog fights, and after every exhausting battle the men return to their dispersal hut, only to find another of their number missing. Unwilling to surrender, the pilot and his comrades unite to take to the skies once more, determined to defend not only the airfield, but their entire country.

Wartime tale of a group of British scientists efforts to develop the first radar system. They did it just in time for it to be used in the Battle of Britain against the might of the Nazi Luftwaffe. Without it the little island could well have been overrun.