Bright, inventive Carl and his dad try to out do each other with practical jokes. They both find this on going competition entertaining, but Mum thinks otherwise. When Dad takes Carl to meet his friend, a retired NASA scientist, he inadvertently gives Carl a top-secret formula. When the professor dies, Carl's world is turned upside down. Carl must summon all his intelligence and inventiveness to keep the formula out of the wrong hands and unravel the mystery of the break-ins and kidnapping. Suggested level: primary, intermediate.