Hayato, temporarily a murder suspect, is released from police custody due to his connections. His further investigations reveal a possible connection between the Skull Man and an arson case ten years ago.
Yui receives a threatening letter and later becomes the target of blackmail. Kiriko follows Yui and Sayoko to the theater. However, the real target of the Skull Man is Sayoko, who turns out to be a mutant.
Hayato and Kiriko hide out in the woods, since Hayato is now a wanted criminal now. It is finally announced that Father Kanzaki is the Skull man, and with his Lost Numbers he would fight the new enemy cyborgs.