On Wednesday 27 May 1942, two assassins waited for a German staff car to round a hairpin bend in a suburb of Prague. Their target was SS Obergruppenführer Reinhard Heydrich, the architect of the "final solution". Heydrich was considered the most dangerous man in Nazi Germany after Hitler himself, and the plot was masterminded in England. Fifty years on, Timewatch examines the planning of the daring operation and the terrible reprisals it provoked.