This is one of my favourite Arthur Conan Doyle's book. I've read several times, I played the HOG game, I saw the movies (I enjoyed Richard Roxburgh as Sherlock Holmes's version... as much as I love him as Moriarty *wink and I can't wait for Benedict Cumberbatch's version) and apparently, my house has several edition of the books... lol... 
 The story is filled with menance, sudden deaths, hidden family secrets, horrifying apparitions that is not apparitions, danger, science and etc that made fanboys glee. The star of this book is non-other than Watson. Clever use of the clues and the story line up quite well. Its not a CSI-kind but enjoyable nonetheless.