In May 1941, Hitler's Deputy, Rudolf Heβ flew solo to Great Britain. The reason for his flight remained a mystery throughout the rest of the War as he brought no new peace proposals, provided no new insight into Hitler's plans, and did not claim political asylum.

In May 1945 and with the war almost at an end, the British Government must decide whether to send the frequently overwrought Heβ back to Germany to face trial on war crimes charges. The government requires somebody whose word carries weight around the world to help with its decision and seizes upon Sherlock Holmes and Dr. Watson as the ideal people to conduct an investigation into Heβ's fitness to face trial and to record the investigation.

Holmes's interrogation of Heβ is a highly dramatic affair and the true reason why Heβ flew to Great Britain is utterly unexpected.

Watson's papers on this case were only discovered in the summer of 2015 and this is the first time they have been published.

It is, however, already clear that "The Führer and his Deputies" will cause the rewriting of history books as, informed by the transcript of Holmes's interview of Heβ, many matters which have until now been obscure, are revealed in a new but wholly convincing light.