A Horcrux is a fictional magical object in the Harry Potter series by J. K. Rowling. It is a Dark Magic device created for the purposes of attaining immortality. The concept is introduced in the sixth novel, Harry Potter and the Half-Blood Prince, though Horcruxes are present in earlier novels without being identified as such. Rowling uses the character Horace Slughorn to introduce their properties. The retrieval and destruction of Lord Voldemort's Horcruxes forms the main focus of the final two books in the series, Harry Potter and the Half-Blood Prince and Harry Potter and the Deathly Hallows.