Good summary of the debunked though still thought-provoking conspiracy theory that inspired a television series and fine Sherlock Holmes film, Murder by Decree (1979) - which I highly recommend if you have never seen - Christopher Plummer and James Mason are so well-paired as Holmes and Watson... I offer an extended and in-depth review at Frame Rated: https://medium.com/framerated/murder-by-decree-1979-blu-ray-studiocanal-vintage-classics-9fef886c5c84