Duke Fleed is the protagonist of the anime series UFO Robo Grendizer. He is a prince from the planet Fleed who has taken refuge on Earth after his home planet was attacked and devastated by the evil Vegan Empire. Assuming the identity of Daisuke Umon, he lives on Earth and works at a ranch while secretly piloting the giant robot Grendizer to protect his new home from the Vegan invaders. Duke is characterized by his strong sense of justice, bravery, and deep sense of loss for his people and planet.