Lord Voldemort owner of Tom Riddle's diary
Harry Potter and the Chamber of Secrets
In the second instalment, Harry Potter and the Chamber of Secrets, Rowling introduces Tom Marvolo Riddle, a manifestation of a teenage Voldemort that resides inside a magical diary found by Ginny Weasley. In this book, Ginny is written as a shy girl with a crush on Harry. Feeling anxious and lonely, she begins to write into the diary and shares her deepest fears with the sympathetic Tom. However, at the climax of the story, when Riddle rearranges the letters in his name to write "I am Lord Voldemort", Riddle is revealed as a magical manifestation of the boy who would later grow up to become the Dark Lord. Riddle states he has grown strong on Ginny's fears and eventually possesses her, using her as a pawn to unlock the Chamber of Secrets, whence a basilisk is set free and petrifies several Hogwarts students. Harry defeats the manifestation of Riddle from the diary and the basilisk. In Harry Potter and the Half-Blood Prince, Albus Dumbledore reveals to Harry that the diary was one of Voldemort's Horcruxes.