Gokuu, who had won the World Martial Arts tournament five years ago, is leading a peaceful life with his wife and son. But the arrival of Raditz, an unfamiliar adversary, changes everything. Raditz claims to be Gokuu's missing brother and exposes that Gokuu is a warrior from a Saiyan ancestry, whose planet was obliterated. Gokuu was sent to Earth as a baby, with the intent to conquer and destroy it, but after losing his memory to a head injury, he was raised as a polite and gentle child who now protects others. Raditz failed to recruit Gokuu as an ally and warns his friends of an imminent danger that could lead to an intergalactic conflict, shaking the universe itself. Dragon Ball Z is a story of a battle over mystical dragon balls, and only the strongest will survive.