Armin Risi agrees that this was to be the great case of Poirot's life, as the character himself claims that all other cases will seem tame by comparison. Poirot does not track down a murderer; he must face and expose a supranational association of high-ranking personalities who are working towards world domination. Risi sees the book as a work of secret history which was inspired by the events and causes of World War I and the October Revolution (the novel was presumably written in 1924 or 1925; see the biographical remark below). The basic scenario of the novel has secret powers (the Four) influencing humanity and the course of history. To Risi it seems to be Agatha Christie's warning about real-life organizations doing the same. He points out that Christie herself may not have been an objective historian. She was a member of the high society in the British Empire. But this fact possibly gave her access to first-hand observers of world politics and the secret affairs behind them. During the interwar period, World War I and the October Revolution were still significant topics of conversation. He theorizes that Christie may have learned of organizations of conspirators active in the era, at least those active in the City of London. There were already rumors that secret forces were planning World War II or even World War III.