As a young adult, Goku meets his older
brother, Raditz, who tells him that they come from a warrior 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 Goku'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.
