Hachimitsu Academy, once an all-girls school, has become co-ed, and teen Kiyoshi is one of five boys to enroll. When he is caught peeping, Kiyoshi is sent to the schools prison, where his punishment is carried out.

Ten years have passed since Goku left his friends and family to hone his skills. But Goku soon finds himself helpless against the mystical power of the Dragon Balls and an accidental wish made by the devious Emperor Pilaf. His desire; that Goku once again become a child! Not daunted by this small setback, Goku, together with Trunks, and his own granddaughter Pan, blast off into the outer reaches of space in search of the mysterious Blackstar Dragon Balls. But these Dragon Balls have a fatal secret: if not collected within one year Earth will be destroyed.

Five years have passed since the fight with Piccolo Jr. and Goku now has a son, Gohan. The peace is interrupted when an alien named Raditz arrives on Earth in a spacecraft and tracks down Goku, revealing to him that that they are members of a near-extinct warrior race called the Saiyans.