The Witch-king is a fictional character from J.R.R. Tolkien's legendarium, primarily featured in The Lord of the Rings. He is the leader of the Nazgûl, also known as the Ringwraiths, who serve the dark lord Sauron. The Witch-king is known for his terrifying presence and is a key antagonist in the story, particularly during the siege of Minas Tirith. Originally a human king, the Witch-king was corrupted by one of the nine Rings of Power given to men. Over time, he lost his physical form and became a wraith, bound to the will of Sauron. His character symbolizes the loss of humanity and the power of evil in Tolkien's world.