Visually alluring and atmospherically seductive, Beauty's distinguished opening shot is the single concessionary ration to the marquee promise of grace and bewitchment. As the lights go down and you settle in, savour it, for such feelings are easily stomach-turned from enchantment to disgust. Over the next 105 minutes, writer/director Oliver Hermanus indomitably puts our noses to the dung pile and forces us to breath deep.

The invasive voyeurism of a seventies style, observatory POV shot is not apparent at first, the bygone era opulence of an Afrikan wedding reception blindsiding us to the gristle beneath the glitter. In actual fact, the Douglas Sirk-meets-Dior décor is perfectly suited, emblematic of the obsessive eroticism that soon consumes the film's boldly unlikable protagonist.

It is from his point of view that the film opens. François van Heerden (Deon Lotz) is surveying his daughter's wedding but only has eyes for his nephew Christian (Charlie Keegan), falling madly in lust from across the room in a rapturously one-sided Ferrero Rocher meet-cute. Lips pursed in a perma-smirk of fastidious disdain for the Apartheid values that deny his sexuality and stoke his rage, François' ugliness succumbs to an image of beauty which he decides there and then, that he must have for himself, respectability be dammed.

In the expressionistic setting and fairytale rhapsody of slow-mo, Hermanus grants François a sense of power – even pleasure – in his doomed infatuation. Aggrandizing a closeted, racist bigot is a tall order but the director and star seem to be very much on the same page in their intent. François stalks the law student and sometime model to skin-crawlingly insidiousness lengths (lying to his wife to visit Christian under shakily false pretences; buying an iPod to win his nephew's favour), almost as sickening as watching him and his deep-in-denial Afrikaner buddies gather at a farmhouse on the edge of town for flesh-sagging, self-hating orgies, from which they ban 'faggots and coloureds' in chest-beating displays of unquestionable masculinity.

At this point it's worth noting that Beauty goes to seedier places that few films dare, and more than a few turned-off walkouts from unsuspecting patrons wouldn't surprise, but for those who can withstand lingering shots of aging hypocrites having angry, squalid sex in the shadows, the repulsion on-screen underscores something deeper than dispassionate shocks or demeaning morals. A world away from the giddy fantasy of the opening, Hermanus trades decorous beauty for restrained, docu-style observation, the remove offering a shrewd look at the disillusioned misery of living a lie. Silently hating that side of himself he can do nothing about is the only safe option for François, whose barely contained anger spills out onto his wife and daughter without warning or explanation, emotional depths beyond discontent reserved only for himself.

It's not until his chance meeting with Christian that François is sufficiently aroused to recognise a basic need synonymous with freedom. Stepping out of the shadows of the farmhouse and into the gay bars of Cape Town, his foolhardy pursuit of a relative who doesn't appear to reciprocate his feelings in the slightest can only ever end dismally, but even as François circles the drain, Hermanus refuses to pass judgement, much less comment in the wake of an inhumane act of sexual violence – a decision that will surely animate many post-movie discussions. Inscrutable authorship leaves Lotz to lay out scant psychological tells, and though he cuts a bullish, intimidating figure, the piggish eyes set back in that hard exterior are all little boy lost. Ravaged by the compulsions of his double life insanity, Lotz exposes a spurned yearning so debilitating that his search for sexual satisfaction at times seems to take on a warped benevolence; a sincere but tragically calculated pursuit of relative self-improvement.

Ennobling a monster is not quite the same as straining to find the humanity in him. In its unredemptive conclusion, no one is saved, no punitive punishments are dished out and no lessons are learned. Uninterested in presenting François in a sympathetic light, Hermanus is nevertheless deeply moved by the plight of his predator, excruciatingly portrayed by Lotz. Whether a packed arthouse on a Saturday night feels the same way remains to be seen, but for those brave enough, Beauty remains compelling viewing best followed by a cold shower.