Kiteretsu Ei is a scientific genius boy who loves inventing stuff, and he aspires to take after his great-great grandfather Kiteretsu Sai, a great inventor in the Edo era. Due to his young age however, Kiteretsu has yet to successfully created anything, until he discovers his ancestor's Encyclopedia and the secret behind them. Thanks to this, Kiteretsu finally managed to create his companion robot named Korosuke, and he vows to bring the rest of Kiteretsu Sai's inventions to light in modern Japan day.