The stranger says that his name is Raditz and that he is Goku's older brother. Goku cannot remember this, as he suffers from brain damage caused by a fall when he was a child. Raditz reports that he and Goku are of a alien race called the Saiyans and that he and Goku are among the last four remaining. He then asks Goku to join them in exterminating the population of Earth, taking Gohan hostage when Goku refuses. Piccolo appears and offers to help him defeat Raditz, Goku accepts his offer and together they follow after Raditz. But then, Goku and Piccolo arrive and confront Raditz, but Raditz is not impressed and tells them that the other two Saiyans are even stronger than him.