This book really is great, it's full of so many different types of cryptograms and codes and it will keep you amused literally all day if you have nothing else to do. I have many cryptogram puzzle books, and this one is the best, by a very long way. Others, while still good, have become monotonous - some more quickly than others - but this one is so varied and interesting, it's not been left on a shelf and forgotton about. It's also clear that it's not just been thrown together in 5 minutes to try and capitalise on the Dan Brown craze (and if it has, hats off to the authors and to Wiley - this really is a very good book!) I can't recommend this book enough, even to people who are put off by the word 'cryptogram' (as I initially was). Especially for the price it is here! There's nothing to lose!