In The Case of the Flying Clown, Paddy O'Shea was an Irish lion tamer of the "Air Thrills Unlimited" flying circus. During a moment of downtime at night, Biggles (who had joined the circus undercover as a pilot) invited Paddy to join him and his colleagues in their trailer caravan for a chat. Paddy told Biggles he never liked the circus clown Nemo, (Jacob Ironmaster)), who appeared to run the circus. Feeling that Biggles and co. were people to be trusted, he revealed aspects of Nemo's past which helped Biggles understand Nemo's motivations and actions. According to Paddy, Nemo was a man with a past. When Paddy was a boy, he was a spare hand at a circus performing in Paris. Nemo was then a tall, handsome man who did a fine act on the high trapeze. One night, however, the rop e broke and Nemo fell, breaking through the safety net, injuring him and disfiguring him for life. Unfortunately, at the time of the fall, the crowd had laughed, thinking it was part of the act. Paddy he would never forget the look of hate on Nemo's face when the crowd laughed. "Knowing the temper of the man, it wouldn't surprise me if one day he got his own back on the crowd."
Paddy's words were prophetic. Biggles subsequently discovered that Nemo had a double identity and he was, in fact, Jacob Ironmaster, a war-mongering billionaire industrialist. And now he would now be back in his guise as Nemo, and about to perform before the dignitaries of the World Peace Conference. This had to imply that he was planning something sinister, probably related to getting his own back at the crowd.