The Germans expected their airborne attack on Crete in 1941 - a unique event in the history of warfare - to be a textbook victory based on tactical surprise.
They had no idea that the British, using Ultra intercepts, knew their plans and had laid a carefully-planned trap.
It should have been the first German defeat of the war, but a fatal misunderstanding turned the battle round.
Nor did the conflict end there. Ferocious Cretan freedom fighters mounted a heroic resistance, aided by a dramatic cast of British officers from Special Operations Executive.