And to the person that said that the last two were too gruesome. Well, they dealt with Jack the Ripper...I would expect them to be gruesome.
Who would like this book? Anyone that loves Victoriana, 19th century history, mysteries, Sherlock Holmes (especially us Sherlockians, I have to say), and/or romance novels. Douglas' "Irene Adler series" has all of these elements and more. It is extremely well written. I consider myself to be extraordinarily literate and I still have to look up some of the terms in this series on occasion. I learn, but I am also entertained. I highly recommend this book as well as all of the Irene Adler series.
Before reading this one, you may wish to read the previous books in the series in this order: Good Night, Mr. Holmes; Good Morning, Irene; and Irene At Large. (As far as I have been able to determine these have not been reissued under different titles but may be in the future). After this book, there are two more books: Chapel Noir and Castle Rouge.