A genre of children's literature which involves stories centered around secrets, puzzles, or unknown elements that need to be solved. These books often incorporate elements of science fiction, introducing futuristic or advanced technology, extraterrestrial life, or altered states of being. The narratives are tailored to engage the curiosity and imagination of young readers, providing both entertainment and educational value through the exploration of various scientific concepts. These books fall under the broader umbrella of children's books and literature.