This documentary is the definitive film on Claus Schenk Graf von Stauffenberg and the Valkyrie conspiracy to assassinate Hitler on July 20, 1944. Produced in collaboration with the July 20 German Foundation and dedicated to the memory of the conspirators (the Forschungsgemeinschaft 20 Juli 1944) as well as the German Resistance Memorial Center, it features testimonials and eyewitness accounts from all leading aristocratic families involved in the plot. These include family members of von Stauffenberg, von Tresckow, von Hofacker, von Hase, and many others. In addition, Operation Valkyrie features the last living conspirator who escaped Hitler's wrath: Philipp Baron von Boeselager, the man who procured the explosives by which Claus von Stauffenberg intended to assassinate Hitler, as well as Maria Countess von Stauffenberg, the last living Stauffenberg who knew Claus all his life. Operation Valkyrie also features leading scholars and historians on the conspiracy, including Prof. Peter Hoffmann, author of the definitive biography Stauffenberg; Prof. Ian Kershaw, renowned World War II scholar and BBC consultant; Prof. Ekkehard Klausa of the German Resistance Memorial Center in Berlin; and Roger Moorhouse, the acclaimed author of Killing Hitler.