A monkey-tailed boy named Goku is found by an old martial arts expert who raises him as his grandson. One day Goku meets a girl named Bulma and together they go on a quest to retrieve the seven Dragon Balls, mythical objects that can summon a dragon who will grant any wish. Along the way, they meet and befriend a plethora of martial artists. They also undergo rigorous training regimes and educational programs in order to fight in the World Martial Arts Tournament, a tournament in which the most powerful fighters in the world compete. Outside the tournaments, Goku faces diverse villains such as Emperor Pilaf, the Red Ribbon Army, a demon known as Piccolo Daimao and his offspring.
As a young adult, Goku meets his older brother, Raditz, who tells him that they come from a race of extraterrestrials called Saiyans. The Saiyans had sent Goku to Earth to destroy it, but his ship crashes upon arrival. Goku fell into a deep ravine and lost all memory of his mission. Goku refuses to help Raditz continue the mission, after which he begins to encounter others who want to battle him, such as the Saiyan prince Vegeta. He also encounters Frieza, who is considered to be one of the strongest beings in the universe, after which Goku begins training his first child, Son Gohan, to be his successor. Years later, a group of soldiers from the Red Ribbon army known as androids appear to kill Goku. Another android,Cell, absorbs Androids #17 and #18 from the Red Ribbon army to increase his power, then fights Goku and Gohan, resulting in the former's death. Goku decides to stay dead for seven years to train in the Other World. When he returns, he is drawn into a battle for the universe against an extraterrestrial named Majin Buu. Joined by Vegeta and Gohan, the evil half of Buu is destroyed and the Good Buu (Mr. Buu) settles down with them. Ten years later at a martial arts tournament, Goku meets evil Buu's human reincarnation, Uub. At the end of the series, Goku takes Uub away on a journey to train him as another successor.