" The Castle of Adventure" is the story of a mysterious uninhabited castle which offers adventure in underground passages and hidden rooms. This is a gamebook connected with the story.
Jonathan and Damian are two boys that like to go fishing with their Granddaddy. On the fishing trips, the boys talk about how they would love to see some big sea creatures. Granddaddy decides to rent a submarine and takes the boys on a trip around the world where they see a variety of sea animals in various locations.