Dragon Ball GT begins when Emperor Pilaf finally gets his hands on the Black Star Dragon Balls, artifacts said to be twice as powerful as Earth's normal set. Hoping to wish for world domination, Pilaf is interrupted by Gokuu Son and botches the request, accidentally turning Gokuu back into a child. The Black Star Dragon Balls then scatter across the galaxy, and Gokuu learns that Earth will explode unless they are all returned within a year. Joined by his granddaughter Pan, a young adult Trunks, and the robot Giru, he travels from planet to planet in search of the Dragon Balls and a way to save his home.
What begins as a spacefaring treasure hunt expands into a larger battle for the fate of Earth and the wider universe. Along the way, Gokuu and his allies cross paths with familiar figures such as Bulma, Vegeta, Piccolo, Majin Boo, and Gohan Son while facing enemies including Baby, Super 17, and the Shadow Dragons. Set after the events of Dragon Ball Z, the series blends comedic adventure with increasingly high-stakes fights as it follows Gokuu through one last era of transformation and cosmic conflict.