Amy and Dan Cahill know their family is big, but they don’t realize how big until their grandmother Grace’s funeral. Relatives arrive from all over the world by special invitation. In Grace’s last will and testament, she issues this challenge:

For your inheritance, you may have the first of thirty-nine clues. The first team to successfully put together the clues, which are scattered across the world, will discover the secret of Cahill power and become the richest, most important people in history. Or you may take one million dollars in cash right now and walk away.

Amy and Dan take the challenge! Soon, they are catapulted into a dangerous round-the-world race for the thirty-nine clues. They will explore every continent, and delve into the strangest, darkest chapters of world history to find the secret origins of their family. Other teams will try to eliminate them by any means necessary, because in this treasure hunt only one team can win, and there are no rules.

The 39 Clues will feature ten action-packed books. The first, The Maze of Bones, is written by Rick Riordan, who also designed the story arc for the entire series. The 39 Clues experience also includes trading cards and a huge on-line game which will allow you to become a member of the Cahill family and compete for amazing prizes! 

Book 2

One False Move

THIS JUST IN! Amy and Dan Cahill were spotted on a train, hot on the trail of one of 39 Clues hidden around the world. BUT WAIT! Police report a break-in at an elite hotel, and the suspects ALSO sound suspiciously like Amy and Dan. UPDATE! Amy and Dan have been seen in a car ...no, in a speedboat chase ...and HOLD EVERYTHING! They're being chased by an angry mob?!? When there's a Clue on the line, anything can happen.Think you've gone everywhere books can take you? Think again. Books are going to a new place, but you have to follow the clues to get there. Join Amy and Dan as they continue the hunt for the 39 Clues in Book Two: One False Note. The high-octane adventures will continue for a total of ten exhilarating books written by well-known authors over two years. The 39 Clues also encompasses hundreds of game cards and an online world that that allows you to play a part in the story and compete for 100s of prizes, totalling over U50,000.