Yow, that was intense. It's a Nikkatsu Roman Porno based on an Edogawa Rampo story, who once again is living up to his Edgar Allen Poe namesake. It's an excellent film, but it's more of a really dark character study than anything with a plot.
It's about a sister and a brother in Tokyo in 1923, Junko Miyashita and Renji Ishibashi. I assumed they were siblings, although they could just as easily be a married couple, or else relatives living together because they share an inheritance. Wikipedia thinks Miyashita is the owner of a boarding house and Ishibashi one of her tenants. Well, it hardly matters. They're both peculiar. Ishibashi is a psychopath who likes crawling into the attic, drilling holes in the ceilings of the rooms below and spying on Miyashita's sexual activities. His face is locked into a permanent sneer and he's uninterested in normal human contact.
Meanwhile Miyashita knows she's being spied on and likes it. She'll have sex with any man available... but with a power twist. You see, she's enormously rich. She has servants and chauffeurs to do anything she wants. She'll go out in a 1920s dress with a parasol, pick up a circus clown and make him copulate with her. She doesn't have sexual partners, but instead uses these people as living sex toys... and they're all her employees. The only man we don't see her seduce is Miyashita, even though she regularly takes pleasure from performing sexual acts while he's spying on her. The most likely explanation, I think, is that there's no power imbalance between them. She can't give him orders. Both treat everyone else around them as their inferiors (Miyashita because she's their boss and Ishibashi because he's slimy). This must surely make them fascinated by each other, as if of a human mirror.
Oh, and she once worked in a brothel. She's didn't have to. "I was only helping out."
It's set in the 1920s, but I didn't realise almost until the end. The period recreation's not bad, but Miyashita's taste is so exotic that I'd assumed we were just in the Land of the Rich. The only difference is that what looks like 1920s retro is in fact contemporary for the characters.
It's a film about sex, but more importantly it's about power. There's a scene where Ishibashi tries to act out something he's seen Miyashita doing, with the help of a prostitute (?) and some clown make-up. It's extraordinary. You've got this overweeningly superior psychopath playing the part of a subservient crawler, although the mask eventually cracks.
There's a sense in which the men around Miyashita are becoming her furniture. There's Ishibashi in the ceiling, obviously, but there's also the pervert's chair. If anyone else was told about that chair, they'd have the perpetrator dragged away by the police. Miyashita finds it a turn-on.
This spirals ever-deeper into insanity. Miyashita gradually slips into a monster, so of course Ishibashi emulates her. It's like one-upmanship. His rehearsals would be the most disturbing thing in any normal film. I don't want to spoil where this goes, but it ended up reminding me of The Fall of the House of Usher, but more twisted. There's an unpleasant hint of the Rape Myth at the end (i.e. that a woman being raped will take pleasure from the physical act, even if it's against her will), but that's not even the third or fourth most disturbing thing about the scene.
Stepping back for a moment, it's the middle film in Noboru Tanaka's critically acclaimed Showa Era Trilogy. The first was
A Woman Called Sada Abe (the softcore one, not Nagisa Oshima's
In the Realm of the Senses) and the third would be Beauty's Exotic Dance: Torture!. Apparently the latter was less well received than its two predecessors because of its extreme sado-masochism. If I can trust what I read, it sounds as if the Sada Abe movie is the most family-friendly of that trilogy. Oh, and all three star Junko Miyashita, who'd joined Nikkatsu with the third Apartment Wife movie and became one of the studio's stars, even being called the second Queen of Roman Porno after Kazuko Shirakawa.
There have been other adaptations of this Edogawa Rampo story, in 1970, 1993 and 2007, but I'd be surprised and impressed if any of them outdid this version. It's all about the psychological descent of its characters and their stifling obsessions and perversions. Tanaka's take on it is pretty much perfect, I think. Appalling, but perfect. The actors' intensity, the wrongness of its sexuality, the hallucinogenic strangeness... this is the kind of thing that's going to depend entirely on whether the actors and director manage to catch lightning. Here, they did. However if they'd failed, the film would have been a boring non-story of idiots doing nothing of interest.
In short: wow. It transcends the fact that it's porn, partly by being so disturbing that you'd have to be as broken as its characters to get off on it. It's also interesting in the way it makes a woman (Miyashita) the most dominating, powerful character in the film. It's not misogynistic. (If our two main characters are siblings, I'm convinced that Ishibashi is the younger of them.) Oddly, the incestuous implications of my hypothesis are largely unimportant and wouldn't really affect the film or the characters' relationship. That should give you an idea of how twisted this gets. It also symbolically kills religion. It's had multiple English-language DVD releases that are still available on Amazon, by the way, so you've got no excuse for not seeking it out.
If you've never before seen a chair masturbate, here's your chance.