Taladhan

Taladhan the Black originally was a young Scholar who worked in the library of Minas Tirith.When Saruman the White came to the Library to research for ancient documents he discovered the talented youth and made him his apprentice.Taladhan followed his new Master to Isengard where he could not withstand to look into the Palantir and spirit became overwhelmed by the Nameless.After Saruman's fall he escaped from Isngard and found refuge in Sarn Goriwing the ancient spire of northern Mirkwood.

the fourth Age
In the fourth Age eventually Alatar, freed from his chains, took over Taladhan's identity.