Exit is about futility and time. Taiwanese Ling (sensitively portrayed by Chen Shiang-Chyi) inhabits prisons.

At 45, she's trapped in a marriage to an absent husband (brilliantly portrayed by the ansaphone message of an uncaring Asian mobile company).

She's trapped looking after her husband's mother, whose only interest (when conscious) is in when her son's coming to see her.

She's trapped in a dilapidated flat in a down-at-heel block, probably forced to live there by her low-paid job as a sewing machine operative.

She hardly talks to anyone.

Trapped, trapped, trapped. Her world is beige. The walls, her mother-in-law's hospital bed, the floors. Even the ageing free sewing machine she's given when laid off by her boss. They all reek of bland, institutional functionality.

Worse still, her skin's a prison. Early-onset menopause has arrived and the sweat of her flushes is painted liberally across the screen.

Everything is hot and close despite her baggy, shapeless clothing. Debut director Chienn Hsiang reveals himself a master of claustrophobia.

The film's soundtrack is filled with the over-loud ticks of modern life. Flip-flops on concrete, the machine gun rattle of Ling's sewing machine and the unsettling creak of her leather handbag.

But it's the unbearable moans of a patient across the ward from her mother-in-law that tug most powerfully. For here we see a glimmer of hope.

Safe in the unseeing gaze of the man's bandaged eyes, she's free to indulge all her pent up passions in the act of soothing his injured body.

For her, stroking his flesh with the special cloth she buys is both guilty pleasure and valedictory escape.

It fuels dormant desires and dangles the possibility of salvation from the putrid funk of living. A dress is created, heels strapped on, dreams enjoyed.

And then an unexpected encounter with the teenage daughter who barely acknowledges her existence day-to-day is enough to plunge her back into the mire. The milk is sour. The bandages come off and her outlet shuts down.

She might be able to get the stuck door to her flat open, but the fight leaves her winded and beaten on the floor. And what's outside anyway, but more of the same?

Exit is not a simplistic piece or an especially comfortable watch. It raises more questions than it answers. Sometimes its narrative thread is confused in favour of tone and style.

But for those who like film to deliver more than the saccharine sweetness Western cinema so often ladles on, it's a must.

Exit, distributed by Facet Film, will be screened at Hackney Picturehouse on Sunday at 12.15. Tickets (£8.60) are available from picturehouses.co.uk.