Project A-ko: Final [プロジェクトA子 完結篇] (1989)
Starring Miki Ito, Emi Shinohara, Michie Tomizawa, Tessho Genda, Shuichi Ikeda, Asami Mukaidono, Daisuke Gori, Sayuri Ikemoto, Yoshitada Ohtsuka
Directed by Yuji Moriyama
I can’t say why the filmmakers decided to call it quits at part 4. Perhaps they ran into funding trouble or just ran out of ideas. Maybe it was a case of staff arguing over the direction of the series. Since I’ve never seen any behind-the-scenes info on the Project A-ko sequels (and probably never will), I can only rely on my own unsubstantiated guesses. For whatever it’s worth, I think they realized there wasn’t anywhere else for the series to go and wanted to end the franchise gracefully rather than milk it until it became a stale echo of its former glory.
One of the reasons I say this is because Project A-ko 4 is basically a rehash of the first film. It once again mainly involves an alien invasion that interrupts A-ko and B-ko’s bickering. In fact, the great feud between the two has become so routine that even the other characters are unfazed by it at this point. The big difference this time is that their teacher, Miss Ayumi, is getting married to Kei, so the fight is over him rather than C-ko. This makes C-ko feel abandoned, and she spends much of the film rather depressed.