I also liked this book better than the first.
This is despite one very significant loose end as well as a twist at the VERY end that didn't work that well. A hint had been dropped earlier, but it wasn't subtle enough.
Anyway, if you are in the mood for a page-turner, this one does the job. If they dramatize it, maybe they should go for a short series to ensure that there is time for historical context and character development.