I am a fan and am predisposed to like her books, but I absolutely loved this! And was really impressed when I read how much research she did (there's a list in her acknowledgments at the end). 
I know very little about Spanish history or the Inquisition but even so she was able to bring a vivid world to life. And while her books are not predictable, there is often a pattern to them AND I am pretty good at guessing plots and yet this one had me guessing up until the very end! I had no idea how this would turn out and was enthralled to the end!