I was really excited to read this book, but about halfway through I just wanted it to end. This book was far too simplistic and broad for its subject matter. The three boys are real cardboard, two-dimensional characters. The trek through the jungle, I thought, just skimmed the surface of the atmosphere it was capable of. In fact, the whole riddle of the codex is nearly forgotten! I'm a big fan of Preston's and Child's writing, their collaberation is terrific. But this one is poor at best.