Melancholia, Lars von Trier, 130 mins (15)

Just how depressed is Lars von Trier, really? As depressed as you'd be, I imagine, if you'd made one of the best films of your career, but no one noticed it because you'd nobbled yourself with a misjudged press conference.

The Dane's facetious "I'm a Nazi" routine in Cannes – which suggested that he's less cinema's John Galliano than its Frankie Boyle – drummed up the scandal that, unusually, his film itself didn't.

Melancholia isn't, this time, a Von Trier shocker – in contrast to the screeching excess of the art-horror ordeal Antichrist. Instead, Melancholia is intimate, surprisingly honest-seeming, and less interested in provocation than in weaving an eerie, troubling spell. Not that Von Trier isn't out for effect, to a degree – he does kick off with nothing less than the End of the World in glorious CGI, our globe pounded to dust as it collides with a bigger planet to the overpowering swell of Tristan und Isolde.

This is only part of an extraordinary opening that's one of the strangest, most beautiful things in recent cinema. Melancholia's prelude is a series of tableaux in uncanny hyper-slow motion: a falling horse seeming to deflate like a balloon; Charlotte Gainsbourg carrying a child across a golf course that has turned to sponge at her feet; Kirsten Dunst in bridal white, entangled in ugly grey tendrils. The whole sequence – photographed by Manuel Alberto Claro, visual effects by Peter Hjorth – resembles a Bill Viola video, and is nothing less than mesmerising.

What follows is rather less cosmic – a diptych of domestic episodes. The first chapter follows radiant bride Justine (Dunst), as she arrives at her wedding party only to find everyone behaving appallingly. Justine's sister Claire (Gainsbourg) and her wealthy husband John (Kiefer Sutherland) are fussing about cost and timekeeping; the bride's mother (Charlotte Rampling) is in a venomous sulk; and her boss (Stellan Skarsgard) is hounding her for an advertising tag-line. Little wonder Justine's one moment of real pleasure comes when she hoists her billowing meringue skirts to take a rapturous piss on the golf course.

This part of the film is briskly comic, like a knockabout remake of Festen, but also decidedly odd: it's supposedly set in America, but you feel you're in a curious semi-Scandinavian non-place, a chateau overseen by a majordomo named "Little Father".

The sparer, more sombre Chapter Two is seen largely from Claire's viewpoint – with Gainsbourg, freed of Antichrist's strident overkill, giving a terrifically affecting performance. We learn that the planet Melancholia is hovering overhead, possibly on a collision course with Earth. Rationalist John, armed with charts and telescope, insists that there will only be a "fly-by", but Justine seemingly knows something that other mortals don't. "The Earth is evil," she snarls. "We don't need to grieve for it." This, the film's most explicitly adolescent bit of doomsaying, is closely followed by the only moment that's unintentionally comic, as Justine samples a slice of her sister's meatloaf, then mumbles: "It tastes like ashes."

Signs and wonders ensue: the horses get spooked; there's a freak snowfall, and a naked Justine basks ecstatically in Melancholia's blue light, like a moonbathing Valkyrie. It all ends with a finale that's as spectacular, and as eardrum-busting, as anything Hollywood could have offered for a similar scenario – although, for my money, this also comprises the film's one genuinely kitsch mis-step.

I defy you not to be moved and troubled by Melancholia on some level, but what is it actually about? Not just melancholia, it seems, but deep, bitter despair – and the attempt to transcend despair by embracing it. But if the film truly stems from Von Trier's personal depression, as he claims, then he comes across like a morose teenager wishing his woes on everyone. Let it all come down, says Von Trier, because humanity deserves the worst – although it's hard to see what Justine's devoted little nephew has done to merit being carbonised.

Amid the luxurious bleakness, Kirsten Dunst gives an extraordinary performance that's all the more remarkable for her role being so mercurial. In the second chapter especially, Justine is a perplexing bundle of shifts and contradictions: one moment euphorically awaiting apocalypse, the next playing a bilious Cassandra, at last turning unexpectedly tender. As in Antichrist, albeit less stridently, Von Trier is marvelling at what he sees as the mystery and horror of woman, and of female knowledge. In any case, Dunst is compelling throughout, from her radiant amusement at the start to the haggard near-catatonia, then Zen-like composure of the second chapter.

Von Trier's detractors may complain that he hasn't really created characters, that he's not seeing beyond himself, and that it's terribly petty-minded for an artist to invoke cataclysm just because he's feeling out of sorts himself. But then Ingmar Bergman made a career of spinning fictions from his own lugubrious worldview, and while Melancholia isn't quite in his league, it's a very Bergmanesque film – severe, graceful, yet mischievous too. Not that the Swedish maestro would ever have resorted to cosmic spectacle of the Michael Bay school. Von Trier, however, is both a showman and a lover of the intimate: only he would pulverise the globe as a preface to a chamber drama about family unhappiness. I don't know if the world will quickly forgive him his Hitler quips, but for Melancholia, I'll even forgive him Antichrist.

Next Week:

Jonathan Romney explores melancholia British style, with Paddy Considine's Tyrannosaur