Your parents leave you and your brother and sister in your grandparents’ care for a long weekend, and they agree to take you to the zip line park or on another adventure! Your grandparents aren’t the type to hide behind the newspaper or fall asleep in an armchair. In fact, they are the most fun people you know. But how well do you really know your grandparents? A man with a briefcase and a scar on his face is watching your every move, and you overhear a very surprising conversation. If your grandparents were also top-secret spies on a dangerous mission, can they still babysit you?!