The wizard who leads the Istari in J.R.R. Tolkien’s Middle-earth is Saruman.
Saruman the White is the chief of the Istari, emissaries sent to Middle-earth to oppose Sauron. He heads the White Council and studies the Rings of Power, Sauron, and the history of the One Ring. His knowledge and authority initially make him the order’s most prominent member.
Saruman’s desire for power corrupts him. He establishes himself at Isengard, breeds the Uruk-hai, and attempts to obtain the One Ring for himself. Tolkien’s story therefore contrasts Saruman with Gandalf, who remains committed to resisting Sauron. Saruman is eventually defeated by the Ents and later expelled from the order by Gandalf, losing the title “the White.”