It begins with a book, the most boring book in the world, a book so boring no one could ever read it—the perfect place to hide a dangerous secret.
When best friends Luke and Tommy volunteer to help move books from their library’s basement to higher ground during a quick rising flood, they discover the only surviving copy of the most boring book in the world: Leonardo’s River, lost for over 100 years. The book is connected to Leonardo da Vinci and is worth millions, so they return that night to steal it. After they steal it from the library, dark forces are soon on their tail. Luke and Tommy must unlock the mystery first, but with their pursuers closing in, the clock is ticking down to the final hour.