He is the Dark Lord, He-who-must-not-be-named. Leader of the Death Eaters, You-know-who is the arch-nemesis of character Harry Potter in the famous book series by author J k Rowling. A half-blood wizard of the worst kind, Tom Riddle, later called Lord Voldemort is known for his trademark disfigured face and long black robe. Novels in this series include Harry Potter and the Philosopher's Stone, Harry Potter and the Chamber of Secrets, Harry Potter and the Prisoner of Azkaban, Harry Potter and the Goblet of Fire, Harry Potter and the Order of the Phoenix, Harry Potter and the Half Blood Prince and Harry Potter and the Deathly Hallows.