Holly's review here.
The first entry in this much-hyped multimedia series was written by Rick Riordan, but fans of the Percy Jackson series may not recognize it. This isn't Riordan's fault: he has a lot to accomplish in this book and not many pages (220) in which to do it, so little things like character development sort of fall by the wayside in favor of a DaVinci Code-like frenzied plotting along with some necessary backstory. All this might sound like I have a negative review, but I really kind of liked it, and I'm regretting that I didn't pick up a few of those trading card packs :)
Amy and Dan's grandmother, Grace, has died and assembled her heirs (an eyebrow-raising group of hundreds, from Korean to Russian to an American reality TV star) to offer them a choice: one million dollars or a single clue. The clue will lead them to other clues, which will lead them to the source of the family's power (most notable historical figures are Cahills, whether or not they know it). Several groups accept this challenge, including Amy and Dan, who convince their babysitter (their parents are dead, of course) to accompany them on their globe-trotting adventure. They are at a disadvantage as the poor Cahills: the Holts are athletic; Irina, an ex-KGB agent, has poison injectors hidden by long fingernails; the Kabras are worldly; Jonah is loved by millions who watch his show; Uncle Alistair is wily; the Starlings are...rich, I think. There are a lot of secondary characters and they never get beyond a single dimension. Amy and Dan were Grace's favorites, so the other teams think Grace must have given them inside information, so they're in danger almost from the beginning. They figure out the clue and head out to find more while avoiding the other relatives. There's a lot of information about Benjamin Franklin, which was interesting and fun. There were some puzzles (look for the page number one!) that were entertaining. It reminded me distantly of Where in the World is Carmen Sandiego?, which i loved as a kid. This is much slicker and shinier (and not on a slow, monochrome computer screen), but the same spirit of adventure and clue-assembling pervades the book/website.
The book comes with six of the collector's cards, and you can buy more. The cards have a code on them so you can create an account and enter them into the web game. Kids ages 6-14 are eligible to win prizes. The website assures parents that there is no communication between players, so it's a safe internet zone for children. While a forum to build teams and share information would be in the spirit of the book (several teams form brief coalitions against their enemies), it's best that they didn't structure it this way. I didn't spend much time on the website, but it seems like a lot of fun. All your cards are displayed, and some have puzzles you can solve for further clues. I would have really gotten into this as a child, and it could be a great spur for reluctant readers to crack open a book. I'll definitely read the second book, which comes out in December.