Prof. Volga was a character who appeared in episode 35 "Dynamite in the Brain!" (頭の中にダイナマイト！). He was a brilliant scientist from West Germany who designed a floating industrial city to be built in Tokyo Bay. Because of this, he was invited to a special meeting of Japan's top scientists. *Spoiler Warning*

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However, he was kidnapped by the Jurals and turned into a human-robot with a bomb inside his head in order to commit an act of terrorism on the scientists. Ken took Prof. Volga and flew away with him to prevent the attack from happening. Later, while Ken was being pursued by the Jurals Ken launched Prof. Volga from his spaceship, saying to him his famous words: Forgive me Prof. Volga! (ボルガ博士、お許し下さい!) Then Prof. Volga flies into the Jurals' ship and explodes, destroying them. Afterwards, in a sad moment, Ken and Prof. Volga's colleague look out to sea at the completed floating city that Prof. Volga helped build. Although Volga died, they completed his floating city properly to honor him in death.