It's always the quiet ones, isn't it? It's always the detached, the reserved and the remote who turn out to be the kinkiest. But then again, if you were in your forties, still lived at home and had a possessive mother, you might be a bit off-kilter too.

The opening to The Piano Teacher sees Erika (Isabelle Huppert), a rather prim middle-aged woman, returning home only to be confronted by her mother. Her mother is outraged that she's late and she wants to know where she's been. She even grabs Erika's purse and checks her bankbook! Erika then grabs her mother by the hair while they call each other names. But after a brief tussle they're in each other's arms, apologising for their behaviour. These two people are highly dependant on one another. And in a weird way they're more like a married couple than mother and daughter; they even sleep in the same bed. Needless to say, it's not a particularly healthy domestic situation.

A description of the opening scene would kind of suggest that Erika is perhaps a shy character, someone who's been bullied ceaselessly by a parent and someone who, as a result, is lacking in confidence. But actually Erika is supremely confident. She's also extremely intelligent and authoritative – her students are in awe of her and are probably more than a little bit scared of her, too. But for whatever reason she's locked herself in this hellish relationship with her mother.

Near the beginning of the film there's a moment when mother and daughter are going to a recital. They get into one of those old-fashioned lifts, and just as they're closing the metal screen, a young man runs to get in with them. They slam the screen shut on him. The outside world is being locked out. However, the young man is going to the same recital, so they meet him again. And the man, who introduces himself as Walter, tries his best to charm Erika. But all the while her mother is watching from a distance with jealous eyes.

Eventually Walter becomes a student of Erika's. However, at first she's not too happy about it. She says he's not motivated enough and she says he's too showy. In a way she's unnerved by him because he's the complete opposite of her. But she's also kind of attracted. When Walter plays at the recital she goes from not being interested to being silently captivated – she even manages something approaching a smile. And then when she becomes his tutor, and after it becomes clear that Walter's interested in her, she follows him after lessons – and again she manages something like a smile when she sees him playing ice hockey.

But the extent of Erika's feelings aren't known until a scene during a concert rehearsal. One of her pupils, a timorous young girl, is supposed to be playing piano. But she turns up late and she's so nervous she's got diarrhoea. This propels Walter into action. He becomes her knight in shining armour; he puts his arm around her, makes her laugh and gives her confidence. But Erika, jealous at the attention her highly-strung student is getting, quietly exits the hall and heads for the cloakroom. She then puts broken glass in the pockets of the girl's jacket. Erika's envy is quiet but deadly.

But Erika also harms herself. There's one scene where she calmly and methodically uses a mirror to cut her genitals. Completely smothered, this is one of her few outlets. But she can't even cut herself without her mother interrupting her by calling dinner. However, Erika is used to this and efficiently cleans up the bathroom. And there's a nice touch of dark humour when the mother sees blood on her daughter's ankle. She thinks she's menstruating and uses that to explain her daughter's mood.

But sex is where the real Erika comes out. In one scene she goes to a sex shop to watch hardcore porn. She even sniffs a pile of used tissues. But what's most telling is how the men in the shop react. They're disturbed (Erika is completely comfortable). They don't want a real woman shattering the fantasies they're there to indulge.

And you could argue that the film is partly about men's unease with female sexuality. For example, Walter worships Erika and says he's in love with her, but when she opens up to him he's disgusted. He didn't know what Erika liked – she writes a letter, telling him her desires; she wants to be tied up and beaten. This doesn't fit into his preconceived idea of her, and as a result, he's thoroughly repulsed.

But what's great about the film is that it doesn't judge Erika. We're not asked to laugh at her or consider her nothing more than an oddity. After all, it's impossible to change someone's sexual desires. No, what's disgusting is Walter's reaction to Erika. She begins to open up to him, to show some vulnerability, and rather than handle the situation like a man and say that he's not interested in that sort of thing, he humiliates her. And he doesn't humiliate her once, he does it a number of times.

And this of course leads to the savagely unhappy ending. Erika is due to perform in a concert, but she waits in the lobby for Walter to appear – she has a knife in her purse. But when he arrives, he arrives in a large group and she can only watch. She then takes the knife and stabs herself. It seems that she's aiming for her heart but she only gets her shoulder. Then she calmly leaves and walks off. She's not dead, but she might as well be; she'll never open up to anyone again.

Directed by Michael Haneke
Written by Michael Haneke
Produced by Veit Heiduschka
Cinematography by Christian Berger
Film Editing by Nadine Muse and Monika Willi
Starring Isabelle Huppert, Annie Girardot and Benoît Magimel

Running Time: 131 mins

Unrated because it features deviant Europeans and stiff cocks