From the first chapter to the last, this entry in the series had me riveted. It was more than just a whodunit, it was also a treasure hunt, and a look into the novel Dr. Jekyl and Mr. Hyde. So many nuances to this story, that I almost lost sleep trying to finish it! The other thing about this series that is absolutely wonderful, The Setting; it is a character as much as the protagonist. It does not just take place In Edinburgh, Scotland; the setting is essential to the plots. The author crafts it so well, you feel like you have been drinking a pint in the pub yourself. And, in this book, you will be taken on a journey to explore its depths. I have to admit to using Google Earth to see the ground myself, and was amazed at how much detail I already had in my head just from the words on the page. And, I found, my head the locations matched Google Earth. How fantastically this author described the scenes! If you have not read any of the previous books in the series, you will not feel lost. The author does a wonderful job of giving enough history behind each of the main characters to let you enjoy the book without spoiling the plots of the others. However, I highly recommend that you do read the others, and if you have read the previous ones, you will be absolutely delighted with this entry. If I could give it more than 5 stars, I would, as I feel this book really was a fun ride for me. In a time where I cannot go many places, this took me away on an adventure, and more.