Lemuel Gulliver
Doctor Syn appears in the "League of Extraordinary Gentlemen" series as a member of the league gathered by Lemuel Gulliver. His alter ego, Captain Clegg, also makes appearances, where he is mentioned to have had a brief romantic liaison with future teammate Fanny Hill. In the 2003 film adaptation of "League", Dr. Syn can be spotted in one of the portraits hanging on the wall in M's library.