Aragorn has a short struggle with Sharku on his warg, where, as Sharku tries to knock him off the warg, Sharku is stabbed in the chest by Aragorn's Elvish knife. The Warg, in an attempt to throw Aragorn off, gallops towards the ledge of a cliff. Sharku then falls off his warg and is trampled. Aragorn becomes stuck to the Warg's saddle and tumbles to his supposed death. Unable to find Aragorn, Legolas and Gimli threaten a dying Sharku who reveals Aragorn's fate before expiring.
Sharku means "old man" in Black Speech and may be a designation that he is an old orc. Saruman's nickname Sharkey was stated in a footnote to be a corruption of the word 'sharku'.