I was probably 50 pages into this book before I realized that it was actually about vampires. Everything I had read was vague, and I had it in my mind that the "family secret" was that members of the family were still practicing torture and impalement in the line of Vlad the Impaler. I'm not into the whole vampire crazy, so I would have stopped at that point had I not been already completely immersed in the story. I'm so glad I kept going because this is what I consider a "real" vampire story - no one is going to high school or sparkling or falling in love with teenage girls - the vampires are scary and evil and lurk in shadows just like they ought to.
I don't know that I would consider The Historian to be a thriller as much as a suspenseful mystery. I love that the author avoids using explicit blood and gore and uses her writing to build the suspense rather than relying on the shock factor. Hitchcock could do wonders with this book. If you're wanting a fast pace, this may not be the best book for you, but, regardless of the slow pace, I was intrigued through the entire novel. My one complaint is that the ending, which a shock, seemed somewhat anticlimactic. After almost 700 pages of buildup, I would have liked a little more to happen with the ending, but it wasn't enough to turn me off the book altogether. It fit the storyline and the author's style well. Definitely recommend it to anyone who loves suspense!