I liked this better than the second book in the series. The puzzles were a little more fun, and I especially had fun with the puzzle that's always at the bottom of the pages. The romantic subplot between Ian and Amy was a bit weird though, to be honest - I know that they're just about on the edge of middle grade - young adult, but I'd probably prefer to keep things focused on the mystery of the 39 Clues. Amy and Dan felt actually fond of each other though, which was an improvement. Overall, I think it's difficult to do what these authors are doing, trading off writing installments and trying to lead toward an overarching mystery.