A unhappily married woman (Audrey Tatou) struggles to break free from social pressures and her boring suburban setting.

Toxic marriage takes Tautou on subtle, powerful descent.

Thérèse Desqueyroux is set in a world of strict morals and fine manners. It is a land of postcard perfection. The folks here take their place in the universe for granted; they reside in the splendor of smoky, rambling mansions of stone, where sunlight struggles to survive. You can almost smell the slow decay.

Miller’s refusal to explain has the effect of sucking us into Thérèse’s own scary impulses

It is a world that is well arranged, designed to protect convention, tradition, the powerful and, as it happens, the small-minded. For this film’s titular hero it is a prison where the insanity of murder makes sense as the only escape route.

The time is 1920s. The place is Landes, France. Here, romance is scorned, and one marries for money and family. Even as a child young Thérèse (Alba Gaia Bellugi) has her life already laid out. Her best friend and neighbour Anne (Matilda Marty-Giraut) tells Thérèse that marriage to her much older brother Bernard Desqueyroux (Gilles Lellouche) is a done deal.

Soon after they are engaged, Thérèse (Audrey Tautou) confesses to Bernard that her head contains 'bad ideas". She extracts a pledge from Bernard: he must, she insists, assist in her purging these wayward, 'unhealthy’ thoughts. He says he will.

Instead, Bernard settles into the marriage as a complacent blob, a bloated and unimaginative little man, happy to be pampered, hunt game and avoid anything approaching true intimacy. The claustrophobia of this life for Thérèse is too much. She conjures morbid imaginings intended to set her spirit free; she imagines her only way out is death. Her marriage to Bernard is like a piece of machinery that grinds away at everything close to Thérèse; even the special bond she has with Anne (Anais Demoustier). In love with a handsome Jewish boy, Anne sends letters full of joy to Thérèse. Disapproving, and fearing what a 'mixed-marriage’ might do to the family name, Bernard enlists Thérèse in a conspiracy to break-up Anne’s romance. Thérèse concedes to this wicked plan out of"¦ an unspoken jealousy? Envy? Duty?

One of the strengths of this quietly powerful film, the last from director Claude Miller, is that the resolution to such questions of motivation are left, tantalisingly, out of reach. There are hints, suggestions, multiple possibilities, but I think this is a movie that disdains such thoughts of certitude as belittling to contemplate too deeply; 'Do you always know why you do things?" asks a character. In the context that line is not intended as a rebuke, but for those who want neatness and closure they’ll find no solace here.

Miller’s refusal to explain has the effect of sucking us into Thérèse’s own scary impulses. She has the look of a character lost to her own soul. When she eventually turns on Bernard, it’s terrible, humiliating. But its true horror lies in the feeling that it was somehow pre-destined, inevitable, perhaps a natural consequence of her existence. That’s a thought to make any self-claiming sane person queasy.

The cast is fine and Tautou’s performance is very good; her external characterisation is a rhapsody of inner pain. Thérèse moves like she is squirming in the grip of some invisible giant; her face is zombie pale and those famously big and lively eyes seemed dimmed and rarely focus on what is present, but are forever searching some horizon known only to her self.

François Mauriac's novel was first published in 1927. It was filmed in 1962 by the great Georges Franju (Eyes Without a Face). I’ve read that the narrative of the book, with its elaborate structure – where the story moves backwards and forwards through time – derived from Mauriac’s interest in cinematic style.

Miller, who did the adaptation, jettisons this technique, electing to straighten out the action. He’s been criticised for this. It slows down the action, but it’s a good way to keep us inside the head of Thérèse. What Miller has done is to find a structure (and a visual style) that is a metaphor for Thérèse’s dilemma; as time moves on her world gets smaller, the pressure builds, hope retreats.

The novel (and the film) can be read as a social and cultural critique, or as is fashionable now, an agonised, disguised self-portrait of Mauriac’s own tragically conflicted sexuality; those 'reads’ are enticing but what Miller has delivered is a slow-burn sun-kissed gothic drama about a kind of madness.

Miller, who died as the movie was completed last year, must have been going through his own special agony while he was making the movie; its images of illness are gut wrenching.

But what strikes me most about Miller’s portrait of Thérèse is that I see little of the 'free spirit’ that critics like to talk about. Thérèse seems tortured and frightened by her self-knowledge. Her lust for liberation is like a slow poison. It makes her sick. For those who know the plot that’s a nice, heavy irony.

Still, for all its gloom, there’s something ultimately stirring about the film, even optimistic. This has as much to do with the desire to see Thérèse get the hell out of this world as it does the film’s superb craft. Cinematographer Gerard de Battista and production designer Laurence Brenguier and co. make an exquisite prison out of the locations; grand country homes, deep pine forest and bruising night skies.

Thérèse Desqueyroux is a movie where brutality is a mind-set and that violence gives rise to dangerous passions. But Miller doesn’t let the story slide into despair. He sees hope and recognises the deep human need to forgive. That kind of decency, in life and in movies, is rare, and its passing is something to mourn.