The fear of rape suddenly befalls women who live peacefully in Shinjuku, as the perspective of the film alternates between the point of view of a rapist who calls himself a "shark" and the women who are raped.
A husband who works as a janitor has a wife who is exhausted by his repeated demands for sex. Frustrated by her refusal he steals chloroform from work and drugs her to get what he wants. But he doesn’t stop there. He decides to try it on any woman he can find.
A policewoman is attacked, handcuffed and raped while on night patrol. Rather than report the incident, she decides to find and punish the rapist herself.