I've been a long-time Scottoline fan, owning all of her books, most in First Edition hardback. I've corresponded personally with Lisa, and she's a charming and very nice person. I've really enjoyed spending time in the world of Bennie Rosato and her associates. It's very painful for me to say that I didn't like this book very much at all.
I understand the artistic urge to take an established character into new and uncharted territory. It keeps it fresh for the author as well as, hopefully, the reader. But as with any risk, there's always the chance of failure.
In general, I don't think much of the doppelganger device in literature and movies. It has been used successfully - and rarely - to illustrate issues of morality and the duality of human nature, but there's a reason the phrase "evil twin" has become such a clichéd joke in our lexicon.
I didn't care all that much for the previous book in which Bennie's twin sister was introduced - it seemed contrived - and this book takes the whole thing way over the top.
The Bennie Rosato of the series is a cool and self-controlled character, with plenty of sang froid to spare, a woman who knows what she wants and how to achieve it. The Bennie in this book is completely unglued, running around like a lunatic with her hair on fire. The pacing and structure of the book reflect this frenzy: my Advance Reader's Copy has 371 pages divided into 128 chapters. Do the math; that works out to 2.9 pages per chapter. This book reads more like a movie script than a novel, and suffers accordingly. There's no real sense of setting in any of the scenes, no inner dialogues to speak of, a pretty complete lack of the kind of narrative of which Scottoline has proven she's capable.
I found the idea that these two women could change places so easily and successfully, given their respective lives, completely unbelievable. The idea that Alice - the "evil twin" - could simply step in and run a successful law firm without any formal legal training was, to me, preposterous.
There were other problems: WAY too much of Mary Di Nunzio's parents, for example, minor "characters" good as comedic foils in previous books, but far too overexposed here. A visiting "Italian aunt" who seems to have psychic powers and serves as a Deus ex machina device. Other things, but I think you get the idea.
Lisa, I know you sometimes read the Amazon reviews. I'm sorry, but I have to call it like I see it.