Terrifying Girls' High School: Women's Violent Classroom was the first of this series, in 1972. Its rough exploitation formula of violence, nudity and scary girl gangs was so successful that Toei made three more the following year:

None of these are sequels and there are no plot links, but they have similar stories and lots of cast and crew overlaps. Reiko Ike was the star of all four and her fellow Pinky Violence icon Miki Sugmimoto co-starred in the first two (i.e. not this one).

The film has two rival girl gangs, of which one is led by the school principal's daughter and so it's under his protection. Both gangs are terrifying. They're amateur criminal organisations (e.g. the shoplifting spree, the pitched battles), although in this particular film they're not running prostitution rings. Mind you, they will attack girls they don't like and strip them naked in public.

There are also American mobsters who arrange fake car accidents. They're rapists. "She was good, wasn't she, Bob?" If you try to get revenge for this afterwards, they'll shoot you in public. They're also racist, e.g. "Get away from me, I hate niggers." That's an enemy worth fighting. The girl gangs are scary, but we'd be cheering for Dracula himself if he was attacking these American mobsters. Also, stacking the deck further still against our anti-heroines, the Japanese authorities want to make life easy for their murdering, raping Western chums.

"It was self-defence. We can't do anything."

"A trifle like this shouldn't harm the friendship between the US and Japan."

I'd recommend all four films in this series. They're as 1970s as you can get, full of sleaze, attitude and brutality. This one has Reiko Ike finding a satisfying tool for the job and delivering exactly what we want at the finale. She was a huge star in films like this in the 1970s and rightly so. She only stayed in acting for a decade, but what a decade. Also, I'm grateful to the filmmakers for finding American actors who spoke pretty good Japanese. This series is in a Japanese movie genre called Pinky Violence (c.f. also Girl Boss and Delinquent Girl Boss) and I have a feeling I'll end up watching all of them.