For a man as methodical and precise about his research as Conan Doyle was, I was extremely disappointed by the grievously incorrect information given in the story as fact, namely about the Mormons and early life in Utah! The story was excellent, until this was introduced to the plot. The author could not even bother himself to spell the names of actual people correctly. I think if he had done a bit more research and told his story better, I may have liked it more, which is a shame because I have enjoyed his other stories so much.