I wish I could give this book 3.5 stars because I have two problems with it: One - the fight scenes are way too detailed for me. Not too graphic, just too technical with how she positions her feet, holds her hand and shoulders while striking, moves her head, repositions her feet, adapts a certain fighting style into her next block, repositions her head and feet at the same time, etc. I found myself getting lost and then skimming to the end of the fight scene to see how it all turned out (they win...a lot).Two - the characters. I didn't feel like any of them were real, including the bad guy, but I'm really hoping the main three characters get fleshed out more in the next book. Which I will be reading because of what I DID like about this book: the research they do trying to solve a centuries-old mystery and all the hidden-in-history clues that come together to form a cohesive and believable picture of the truth. I don't know anywhere near enough about the covered time periods to know if any names (beyond Joan of Arc) were real people, but it sure felt real. The historical clues made sense and were uncovered quickly (archaelogy message boards, phone calls to colleagues, etc.), so no hours hunkered over old texts to slow the super-fast pacing of this novel down. If the next book in the series has more of the same along with further character development, it just might get five stars.