This story begins with travel time for the entire Brewster family as they plan a trip to Hawaii. It includes Bruce ("Biff"), his Mother, and Dad, with the younger twins, Ted and Monica. It's really exciting for the twins because they have never been outside the continent. One of Dad Tom Brewster's chief reasons for the journey is a planned meeting with Dr. Johann Weber, scientist and staff consultant for Ajax Mining Company. They were expecting to meet Weber on arrival but a shocking surprise was ahead. Passing a newsstand when they reached the Honolulu airport, a newspaper had a major headline: "Dr. Weber, Famous Scientist ... Missing!"

Early indications indicate kidnapping with Weber's life at stake due to an extremely important scientific project. Among the many problems are a sunken sloop and a hidden stash of Cesium, an extremely rare mineral used to propel rockets. There are indications an unscrupulous group plans using it to make a conquest of the moon. Biff and his dad get unexpected help from a new friend of Biff, Likake Mahenili, a skilled diver known as Lee to his friends. We can listen and discover for ourselves what took place around the islands.