I have not read Philippa Gregory's books before, although I have two in my TBR pile. Rather than recount the plot, I will simply give what I found to be the strengths and weaknesses. Actually, there is only one weakness and it's minor.

The book is a historical fiction. The time period is when Christendom was falling apart as far as the Pope's extension of it. Luca is a young inquisitor who is inexperienced but willing to do what is right. His character is established quickly and he stays true to that persona. In fact, all of the main characters are well developed and stay true to their personalities. Peter is the experienced nay-sayer, Frieze, I can't say enough good about. He plays the intelligent fool who, when told to stop talking, he simply makes comments to his horse, instead. I loved him. Isolde is an unfortunate but strong protagonist who, with her Moorish companion, Ishraq, is a force to be reckoned with.

Although this is a series, the first book, at least, can stand on its own. It is the adventures of Luca who is following his assignments of inquiry which brings him to the Abbey where Isolde is Abbess. This story had me hooked completely. It was well developed and revealed, the character's interactions and lines well timed and delivered, and resolved nearly completely. That "nearly" gives the book a continued drive.

The only part I found weak was the last adventure as I thought it was too obvious and drawn out. On the other hand, we became much more acquainted with Ishraq and I look forward to more books and adventures with the characters. I really loved them.