Saruman is the most powerful of the group of wizards in Middle Earth named the Istari. He betrayed them for his own selfish ends in an attempt to overthrow the Dark Lord, Sauron of Mordor. Saruman abandoned his former white cloth for a a decadent multi-colored robe, declaring himself Saruman of Many Colors. He created an army, a special breed of orc known as Uruk Hai. The Uruk-Hai were larger, stronger and more resistant to sunlight than the orc clans of Mordor or Moria. Movie adaptations often depict him as a servant of Sauron, but usually this is merely a ruse while he secretly plans to claim the Ring for himself. He failed because of the efforts of rival Maiar Gandalf, Treebeard, and Theoden, the king of Rohan.
Saruman eventually left his tower and conquered the Shire out of spite, forcing the Hobbits into slave labor and drug trade. The four hobbits returned after the war to witness his servant, Wormtongue stab Saruman in the back and his spirit promptly fled the land. Saruman was unable to return to the West due the genocidal crimes he committed after abandoned the task he was sent to accomplish as former leader of the Istari order.
Saruman has the ability to manipulate other people with magic using only his voice. He can use the power provided by his staff to attack others with violent magic blasts. In the movie Fellowship of the Ring, He has also been observed controlling the weather in order to try and stop the Fellowship from continuing their quest.