In Biggles Foreign Legionnaire, Hugo Festwolder was one of the "Committee of Three", the group of financiers who controlled the operations of the war-mongering syndicate in the background. Festwolder was described as large of stature, with red hair and big red whiskers. During the Second World War, he had been one of the industrialists who backed Hitler, but he had been clever enough not to have done so openly. At the time of the events in the book, he was still in the arms trade but specialised in supply arms to all kinds of unlawful elements.
Towards the end of the book, with most of the senior officers of the syndicate, Johann Klutz, Voss and Leffers dead, and one of the three committee members Nestor Janescu also murdered, Festwolder and his remaining partner Fabiano Pantenelli had no choice but to emerge from the shadows to direct syndicate operations themselves. Together with Erich von Stalhein whom they had newly engaged to run the secret squadron, they were flown out to the Valley of the Tartars by Liebnitz on the committee's Douglas DC-3. Festwolder was subsequently killed when Kurd tribesmen attacked the secret squadron base.