He was the Duke of Clarence. Or maybe Dr. Gull. Or perhaps Montague John Druitt. Or Joseph Barnett, or Alfred Napier Blanchard, or W.H. Bury, or Lewis Carroll (!), or David Cohen, or Dr. T. Neill Cream, or                 Frederick Deeming. Then again, he might have been Fogelma, or George Hutchinson (Br.), or James Kelly, or Severin Klosowski (George Chapman), or maybe Aaron Kosminski, Jacob Levy, James Maybrick, Michael Ostrog, Dr. Pedachenko, Walter Sickert, James Kenneth Stephen, R. D´Onston Stephenson, Francis Thompson, Francis Tumblety, or Nicholas Vassily. Or he might have been a she. Or maybe none of the above.

Personally, I think that Jack the Ripper was Sherringford Holmes, Sherlock's evil twin.