Jin Kurono's father is dead, so he has been raised by his mother, who taught him the sense of honor and justice. But she died, killed by a car, with the culprit running away after the accident, leaving a scar on Jin's heart. Now, he's 23 years old, and the programmer of a new game called Zetman. Upset with the fact that there is no justice in the real world, he turns into his own superhero Zetman, to fight against crime, but with hard methods. To advise him and support him, he will always have his best friend, Sachiko Shirai.

> Trivia: The manga is a collection of 4 oneshots, published between 1989 and 1994 in Shueisha's Weekly Shounen Jump magazine:

1) Zetman (original version)

2) Shin-no-Shin ~Ai to Nikushimi no Time Slip~ (SHIN-NO-SHIN 愛と憎しみのタイムスリップ, Shin-no-Shin: A Time Slip of Love and Hatred)

3) Woman in the Man ~Otoko no Naka no Onna~ (WOMAN IN THE MAN -男の中の女-)

4) Shadow Lady (1993 ~ first version)