First in a two-part documentary in which historians consider occasions when the Second World War might have been avoided, and the nature of the policy of the appeasement prior to, and in the early stages of, the war. Above all the film explores the failure of politicians and citizens alike to understand the real threat that Hitler posed.

Part two of two. Historians continue to debate whether Hitler could have been stopped as they discuss the nature of the policy of appeasement prior to and in the early stages of the Second World War.