When Arthur Conan Doyle was a lonely 7-year-old schoolboy at pre-prep Newington Academy in Edinburgh, a French émigré named Eugene Chantrelle was engaged there to teach Modern Languages. A few years later, Chantrelle would be hanged for the particularly grisly murder of his wife, marking the beginning of Conan Doyle’s own association with some of the bloodiest crimes of the Victorian and Edwardian eras.