The Underwater Story saga consists of five stories: Ludwig, the King of Daminia; Underwater History; Leda and Metida; Kalida the Witch; and Marcus the Mouse, which are linked by a common plot, characters, and story time. The main theme of the saga is the battle between good and evil. The author's intention is to show the strong friendship and fearlessness of the heroes, their mutual help, faith in the victory of good over evil, the need to keep one's word, and perseverance in achieving the goal.