Like Dan Brown, Neville uses a few historical facts and events to base her story on. If you liked "Code" you'll probably go for this one too. It's a multi-level story of the hunt for Charlemagne's Chess set, which according to legend has magical powers. So pull up a beer (or iced tea) and some chips, it's gobnna be a long evening's entertainment.
This is a most excellent engrossing book. One of my very favorite. The two time periods and European history, chess tournaments, puzzles and codes, long before The DaVinci code.