Cam Jansen and the Secret Service Mystery

David A. Adler's Cam Jansen series has produced numerous best-sellers and been a consistent favorite with young readers. In this exciting adventure, a presidential election campaign brings the governor to Cam's school. With all the police and Secret Service agents, it seems like nothing can go wrong. But then there's an explosion that sounds like a gunshot, and Cam determines to get to the bottom of what really happened.