Abby and Peter pay a visit to their Uncle Jonathan who seems very knowable about Egyptian mummies, but they become suspicious at the strange sounds coming from a room inside his house, and their fears continue as they are invited to Horrorland.
Billy and Sheena go with their Uncle, Dr. Deep, to search for treasure and are pursued by pirates who have been dead for two hundred years, and when Billy and Sheena return to land and visit Horrorland they encounter their worse fears.