Space Ace is the story of an alien young boy named Space Ace (or Ace for short), given to homesick stargazing with the faces of his loved ones ghosted across the heavens. His tool of preference is the galaxy ring, a flat white hoop he can produce from his fingers to be thrown or ride on. The supporting cast includes Dr. Tatsunoko, who is almost a father figure to Ace, and his daughter Asari, Ace’s love interest. Providing the show's comedy relief was crusading investigative reporter Yadokari, who usually burst on the scene riding his jet skycycle at the worst possible moment, screaming for Ace to give him interviews and so on. One of the show's most important characters is "Ebo", Ace's imagined projection into the night sky depicted as a humanoid robot.