Underground people who exhale toxic gas appear in Tokyo's S-Ward, which is dealing with construction noise from urban development projects. Everyone panic, but it turns out that five middle-aged guys are unaffected by the poisonous gas. They undergo vigorous training to fight the underworld people, but are they going to be able to save the world…?
A young high school Yanki (Japanese delinquent), Tokio, gets suspended from his school and ventures out to Ikebukuro. Aiming to become a janitor for at a love hotel, he eventually gets scouted to join a gang. They make money ripping people off, and Tokio begins to question his own actions. The gang thinks all is well, unaware of the bigger threat that awaited them.