In May 1940, Hitler's Panzers trapped the armies of Britain and France in a pocket of land around the French port of Dunkirk. Escape seemed impossible, but within nine days more than 300,000 of these men were safely ashore back in England. How, against all the odds, had nearly a third of a million men been rescued from the beaches? Using eye-witness accounts and archive film, Timewatch recalls the political and human dilemmas which, 50 years ago, dominated an incredible nine days in British history.