"The German invasion of England took place in July, 1940 after the British retreat from Dunkirk. Strongly resisted at first, the German army took many months to restore order, but the resistance movement, lacking outside support, was finally crushed. Then, in 1944, the resistance movement reappeared..." This is the starting point for Brownlow and Mollo's remarkable story of occupation and collaboration in Nazi-controlled England. Their rewrite of history is all the more effective for having the appearance of absolute authenticity. Uniforms are genuine, the voices heard in newsreels are those of BBC wartime announcers, and the background details of posters and newspapers were meticulously researched. Amazingly, not a second of stock footage was used. Brilliantly edited, it gives an authentic feel of how things might have been in occupied England had the Nazis invaded. At the heart of the film's central story of a district nurse trying to practise her profession is the dilemma that if you don't take sides in wartime, then you are seen to collaborate.