HHhH:  "Himmlers Hirn heisst Heydrich”, or “Himmler’s brain is called Heydrich”. The most dangerous man in Hitler’s cabinet, Reinhard Heydrich was known as the “Butcher of Prague.” He was feared by all and loathed by most. With his cold Aryan features and implacable cruelty, Heydrich seemed indestructible—until two men, a Slovak and a Czech recruited by the British secret service, killed him in broad daylight on a bustling street in Prague, and thus changed the course of History.