Piccolo is honing his skills on a deserted cliff when a group of unknown foes ambush him, overpowering him with ease. These assailants subsequently infiltrate Mount Paozu, aiming to pilfer Gohan Son's "Dragon Ball." In their quest, they vanquish Gokuu Son's wife and father-in-law, Chi-Chi and Gyumao, respectively, and take Gohan captive. Sensing that something is amiss, Gokuu hurries back home and finds Chi-Chi injured on the ground, who fills him in on the situation. Determined to rescue his son, Gokuu heads to Kame House and borrows the Dragon Radar to trace the Dragon Balls, which will lead him to both the adversaries and Gohan.