Disclosure: I haven't ever read HP Lovecraft. If I were an HPL fan, maybe my review would be different.
This book is chaotic, nonsensical, messy, and super gross. (I don't think I've ever read a book that features pus so prominently.) Early in the book, Holmes and Watson discuss how mathematicians aren't ever criminals. Yeah...except Moriarty is a mathematician. And he's mentioned several times in this book. I will not read the second one.