Born in Halle in 1904 to a family that ran a music conservatory, Reinhard Heydrich was a frail, high-voiced teenager bullied over rumours of Jewish ancestry. Drawing on SS personnel files, Wannsee testimony and biographies, this episode follows his path from nationalist paramilitary youth to naval cadet, his dismissal from the Navy in disgrace after a broken engagement, and the interview with Heinrich Himmler that his fiancee Lina practically forced to happen. From a single shared typewriter, Heydrich built an intelligence apparatus on colour-coded index cards, an analogue surveillance database used to blackmail and destroy rivals.

We trace how he weaponised that system in the Night of the Long Knives, invented protective custody to place the Gestapo outside the law, staged the Gleiwitz false-flag attack that gave Hitler a pretext to invade Poland, micromanaged Kristallnacht, deployed the Einsatzgruppen, issued the Night and Fog decree and chaired the Wannsee Conference like a corporate board meeting. The episode ends in Prague with his carrot-and-stick rule, the hubris of driving an open-top Mercedes on the same route each day, Operation Anthropoid, the jammed Sten gun, the fatal decision to stop and fight, his death from sepsis in June 1942, and the annihilation of Lidice and Lezaky in retaliation.

• How childhood insecurity and ancestry rumours drove Heydrich toward ever more extreme fanaticism
• The index-card intelligence network that turned raw information into political terror
• Operation Himmler at Gleiwitz and the bureaucratic coordination of Kristallnacht
• Why he secretly flew nearly 100 combat missions until Hitler grounded him
• The assassination in Prague, the refusal to use sulfonamide antibiotics, and the reprisals that followed