Frodo the hobbit is back to battle the evil forces that have invaded Middle Earth. This continues the quest for the now-villainous Ring. Frodo vows to destroy the Ring, even if it costs him his own life. He pursues the Ring to the inside of Mount Doom, a volcano. He does this on behalf of good-guy Aragon, who will never be able to escape the dreaded land of Sauron so long as the Ring retains its evil powers.