I was rather disappointed in this book. I loved the first two, and had been looking forward to this book since I read #2, but it just didn't meet my expectations. It seemed very anti-climatic. The whole time I was reading it, I was wondering if it was even written by the same person. The whole thing with Gallowglass (view spoiler)[ being in love with Diana (hide spoiler)] seemed like a convenient way to get rid of him while still being able to bring him back when needed. And as for Ashmole 782: the whole series is basically about this book. When it's finally found and restored, there's no answers - no explanation on its origins and only hints of what it actually contains. 
 This book wasn't horrible; it just wasn't as good as I was hoping.