Tough girl biker Ako (pop singer Akiko Wada) comes across Mei (Meiko Kaji) and her girl gang (the Alleycats/Stray Cats) as they are about to have a knife fight in Shinjuku, Tokyo with another gang of girls. When the second gang calls in their boyfriends for help, Ako joins in and turns the tide for Mei and her gang and becomes a leader figure for the girls. Meanwhile, Mei's boyfriend Michio (Koji Wada) wants to join some right-wing nationalists, the Seiyu Group. To prove himself, he induces an old friend Kelly (Ken Sanders) to throw a boxing match so the Seiyu Group can cash in betting against him. But when the boxer, encouraged by Ako and Mei, wins the fight, the Seiyu Group takes their anger out on Michio until Mei and the Alleycats rescue him. But Mei and the girls are now on the run from the powerful group. Mei is eventually killed and Ako leaves Shinjuku, roaring away on her bike.