Lurtz was the first of Saruman's Uruk-hai to be bred, and led them into battle against the Fellowship of the Ring at Amon Hen. Lurtz also appeared to be the largest Uruk-hai. In the book, Boromir is slain by an unnamed orc or orcs; he is described as having been "pierced by many arrows". In the movie he is killed by Lurtz, who shoots him three times. Aragorn then intervenes, and after a brief fight stabs Lurtz and then removes his head. In the book Uglúk was the leader of the orc-band from the beginning.
Lurtz's name is never spoken aloud in the film, and is only known from the franchise and credits. Despite some initial fears that he was an entirely new character, he really wasn't much different from other 'generic Orc leaders' already present in the book.
The character of Lurtz is one of the playable "heroes" in the computer game The Lord of the Rings: The Battle for Middle-earth.