Dragon Ball Z: The World's Strongest

The movie begins with Gohan and Oolong searching for the Dragon Balls that have all been gathered in the frozen Tsumisumbri Mountains (with the latter obviously wanting to wish for underwear). Before they reach them, Shenron is summoned by Dr. Kochin, who wishes for his mentor, Dr. Wheelo, to be released from his icy prison. Meanwhile, Piccolo is ambushed by three mysterious warriors and knocked out cold while trying to defend Gohan and Oolong. Later on, Gohan has a weird dream about him and Piccolo.

Kochin then kidnaps Master Roshi and Bulma, thinking that Roshi is the world's strongest and a suitable body for Wheelo, whose own body was destroyed, leaving him only as a brain. Roshi is tested by Kochin's Bio-Warriors, and, despite putting up a decent fight while being outnumbered three to one, is ultimately defeated. Bulma then reveals that Goku is the strongest, just as he approaches Wheelo's fortress to save his friends. Meanwhile, Goku and Chi-Chi confront Oolong and Gohan on what they know about the group who kidnapped Bulma and Master Roshi.
Krillin's arrival in Wheelo's fortress
Added by Devlin85

After reaching the fortress, Goku is attacked by the Bio-Warriors, but easily defeats them with the Kaio-ken, and is also joined by Gohan and Krillin. They then arrive at Wheelo's lab where Bulma is being held, but run into Piccolo, who was brainwashed into returning to his old ways when he was captured earlier. Goku and Piccolo then fight each other, but Gohan's anger causes the mind-controlling device on Piccolo to break. Kochin tries to shoot Krillin and Bulma with his machine gun-arm, but is beaten by Roshi.

Wheelo then breaks out of the wall, revealing his brain to be inside a huge robot. Realizing that he was being controlled, Piccolo attacks Wheelo, only to be brushed aside. As Wheelo jumps into the air, Goku, Krillin, and Roshi fire the Master-Student Kamehameha, which does nothing to Wheelo. Goku, Gohan, Krillin, Piccolo, and Roshi then attack Wheelo, but are unable to win. Goku then fires his Kaio-ken Kamehameha and shoots Wheelo into space. Wheelo decides to destroy the Earth with his Planet Geyser energy wave and move on to another world, but Piccolo and Gohan are able to stop him for a while. Meanwhile, Goku has been collecting energy for a Spirit Bomb; when it is ready, Goku launches it at Wheelo and destroys the mad scientist.

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