liaison and voyaged to Italy together. During this dalliance, Reilly apparently "bared his soul to his mistress," and revealed to her the story of his strange youth in Russia. After their brief affair had concluded, Voynich published in 1897 her critically acclaimed novel, The Gadfly, the central character of which, Arthur Burton, was allegedly based on Sidney Reilly's own early life. In 2004, writer Andrew Cook suggested that Reilly may have been reporting on Voynich and her political activities to William Melville of the Metropolitan Police Special Branch. In 2016, new evidence surfaced from archived communication between Anne Fremantle, who attempted a biography of Ethel Voynich, and a relative of Ethel's on the Hinton side. The evidence demonstrates that a liaison of some sort took place between Reilly and her in Florence, 1895. Popularity With the central theme of the book being the nature of a true revolutionary, the reflections on religion and rebellion proved to be ideologically suitable and successful. The Gadfly was exceptionally popular in the Soviet Union, the People's Republic of China, and Iran, exerting a large cultural influence. In the Soviet Union, The Gadfly was compulsory reading and the top best seller; indeed, by the time of Voynich's death, The Gadfly is estimated to have sold 2,500,000 copies in the Soviet Union alone. Voynich was unaware of the novel's popularity, and did not receive royalties, until visited by a diplomat in 1955. In China, several publishers translated the book, and one of them (China Youth Press) sold more than 2,050,000 copies. It was banned, however, after the Sino-Soviet split. Irish writer Peadar O'Donnell recalls the novel's popularity among Republican prisoners in Mountjoy Prison during the Irish Civil War. The Russian composer Mikhail Zhukov turned the book into an opera The Gadfly (Овод, 1928). In 1955, the Soviet director Aleksandr Faintsimmer adapted the novel into a film of the same title () for which Dmitri Shostakovich wrote the score. The Gadfly Suite is an arrangement of selections from Shostakovich's score by the composer Levon Atovmian. A second opera The Gadfly was composed by Soviet composer Antonio Spadavecchia. On the other hand, in Italy, where the plot takes place during the Italian Unification, the novel is totally neglected: it was translated into Italian as late as in 1956 and was never reprinted: Il figlio del cardinale (literally, The Son of the Cardinal). A new edition, carrying the same