Operation Bernhard was the largest counterfeiting operation in history, run by the SS and carried out by Jewish prisoners inside the Sachsenhausen concentration camp. This episode begins with Arthur Nebe’s 1939 proposal to rain 30 billion fake pounds on Britain, the technical work of reverse-engineering rag paper, ultraviolet fluorescence, hidden marks, and serial-number algorithms, and how office politics derailed the first effort before Himmler revived it as a black budget for espionage.

It follows SS Major Bernhard Krüger’s recruitment of engravers, printers, and bankers, the strange conditions in Blocks 18 and 19, and the aging department that pricked and folded notes to make them look used. The conversation covers money launderer Friedrich Schwend’s one-third cut, the order to forge the US $100 bill, the prisoners’ deliberate slowdown, the crates dumped in Lake Toplitz, the broken-down truck that spared 140 men from execution, and the redesign of the British five-pound note in 1957.

• Why German water had to be chemically altered so the paper would glow correctly under UV light
• How Krüger’s extra rations and ping-pong table were a management strategy rather than kindness
• Four grades of forgery and where each one went
• Why both the prisoners and their SS commander wanted the dollar project to fail
• What happened to Krüger and Schwend after the war, and the treasure hunts in Lake Toplitz