I won't enter into the debate comparing the Joshua Files to the Bourne movies - the key point is that this book is an absolutely brilliant read in its own right. Actionwise, it starts strong, builds, and then takes off with the kind of page turning intensity which makes you want to skip meals and read all night. 'Read page 37', instructs the back cover - believe me, on page 37 we're barely into second gear; it's good, but it gets a whole lot better.
I'll repeat the observations of other reviewers here and comment that all this action is deftly balanced with an exceptionally strong characterisation. The result is that it isn't just exciting to accompany Josh on his adventures - we actually understand him and care what happens to him all the way through. My eleven year old daughter, not a pure action or sci fi fan, is riveted by the power of the emotional story.
Another perfect balance is achieved in the level of challenge the book presents to the reader. Of course there's the code woven into the book, and the prizes offered on the book's website for cracking that. Beyond this there are enough ideas and information thoughout to spark the curiosity of the most active mind. It's easy to find the Author's website and begin one's own fascinating exploration of Mayan mysteries. At the same time the writing style is so direct and accessible, that even a reluctant reader can just relax and enjoy the simple thrill of the story.
Finally, I have to mention the slip cover. It's not often one gets a 'wow!' reaction just from walking around holding a book. Honestly, go and look at one in a shop. Buy one now, for yourself or your kids, and be the envy of all.