"The Supernaturalist" is a science fiction novel by Eoin Colfer that follows a young boy named Cosmo Hill. He escapes from a dreary orphanage and discovers a group of misfits who can see supernatural beings called Blue Spirits. Together, they embark on a mission to uncover the truth behind these spirits and their connection to the world. The story explores themes of friendship, adventure, and the struggle against a corrupt society. As Cosmo and his friends face various challenges, they learn about their own abilities and the importance of standing up for what is right in a world filled with danger and deception.