Lord Voldemort ( , in the films) is a sobriquet for Tom Marvolo Riddle, a character and the main antagonist in J. K. Rowling's series of Harry Potter novels. The character first appeared in Harry Potter and the Philosopher's Stone, which was published in 1997, and returned either in person or in flashbacks in each book and its film adaptation in the series except the third, Harry Potter and the Prisoner of Azkaban, in which he is only mentioned. Voldemort is the archenemy of Harry Potter, who according to a prophecy has "the power to vanquish the Dark Lord". He attempts to murder the boy, but instead kills his parents, Lily and James Potter, and leaves Harry with a scar on his forehead in the shape of a lightning bolt. Nearly every witch or wizard dares not utter his name and refers to him instead with such monikers as "You-Know-Who", "He Who Must Not Be Named", or "the Dark Lord". Voldemort's obsession with blood purity signifies his aim to rid the wizarding world of Muggle (non-magical) heritage and to conquer both worlds, Muggle and wizarding, to achieve pure-blood dominance. Through his mother's family, he is the last descendant of the wizard Salazar Slytherin, one of the four founders of Hogwarts School of Witchcraft and Wizardry. He is the leader of the Death Eaters, a group of evil wizards and witches dedicated to ridding the Wizarding World of Muggles and establishing Voldemort as its supreme ruler. Character development In a 1999 interview, Rowling said Voldemort was invented as a nemesis for Harry Potter, and she intentionally did not flesh out Voldemort's backstory at first. "The basic idea [was that Harry] didn't know he was a wizard ... And so then I kind of worked backwards from that position to find out how that could be, that he wouldn't know what he was. ... When he was one year old, the most evil wizard for hundreds and hundreds of years attempted to kill him. He killed Harry's parents, and then he tried to kill Harry—he tried to curse him. ... Harry has to find out, before we find out. And—so—but for some mysterious reason the curse didn't work on Harry. So he's left with this lightning bolt-shaped scar on his forehead and the curse rebounded upon the evil wizard, who has been in hiding ever since." In the second book, Rowling establishes