UFO Robo Grendizer

Duke Fleed is one of the few survivors of Planet Fleed after the Vega Empire destroys his homeland. Escaping to Earth aboard the mighty robot Grendizer, he is taken in by Dr. Umon and begins a new life under the name Daisuke Umon.

Years later, Vega's forces reach Earth and threaten to repeat the tragedy Duke once escaped. He can no longer remain hidden. Together with Koji Kabuto, Hikaru, and later his younger sister Maria, Duke takes control of Grendizer to defend his adopted home while carrying the memories of the world he could not save.