Let me start off by saying that if you haven't read any of Gerritsen's books featuring her two main characters, don't even consider reading this book. So much about the characters deeply depends on your being familiar with their history. Even if you have read other books with these characters, The Mephisto Club, while starting off with a lot of suspense, is a disappointment. The plot drags and requires you to suspend belief way too much, there are too many subplots that are left dangling, and the ending -- what there is of one -- is weak and unsatisfying. All in all, I'd advise you to skip The Mephisto Club. Your time and money are too valuable to spend on a book that, at best, is mediocre.