39 Clues is a book series written by Rick Riodan. I just read the first one and it is called The Maze of Bones. I liked the book because it has action and suspense. It was one of the best books I have ever read. I plan to read all 39 books in the series. The main characters are a boy and his sister. Their names are Dan and Amy. Amy is older than Dan but Dan seems smarter. Their friend Nelly is taking them all over the world. Their parents aren't the ones doing this because they died in a fire. Their Grandma Grace died and she left them the 39 Clues. But the some of the Cahill family was competing against them. They were competing against them because after the 39 clues are found, that team or person will become the more powerful Cahill in history. According to this book, Abraham Lincoln, Lewis and Clark, George Washington, and Benjamin Franklin are all Cahills. There are 4 sections. I forget what they are but the one Benjamin Franklin was in was usually the meanest. But every once and a while, that group did something right. That is why I love this series. Lots going on and I haven't even read the second book!