SPENCER

It's almost impossible to comprehend the idea of Diana, Princess of Wales. Few figures within our lifetime have been as beloved, as dissected, as deified or, ultimately, as unknowable. She seemed a bridge between the marble world of tradition and monarchy and the dreams of a better future, embodied in a woman of astonishing beauty, bounteous humanity and indescribable sorrow. There have been many attempts to capture that lightning in a bottle quality on-screen, but with the exception of Emma Corrin's brilliant turn on the most recent season of 'The Crown', all have failed. When it was announced that acclaimed Chiléan director Pablo Larraín would direct 'Spencer', an imagining of the beloved icon with the great Kristen Stewart in the role, it was impossible not to be intrigued. Larraín's 2016 masterpiece 'Jackie' was an astonishing portrait of Jackie Kennedy, another iconic woman of the 20th century whose life was shaped by tragedy and duty. If Larraín could bring the same brilliance to 'Spencer', it might be something truly special.

Before the film begins, we see a title card that reads, "A fable from a true tragedy", and this positioning of 'Spencer' as a fable rather than a biopic is important to understanding its strange, beguiling magic. Set over the three days of Christmas celebrations in 1991, the film imagines the final weekend Princess Diana (Kristen Stewart, 'Personal Shopper') would spend with the British Royal Family at their estate in Sandringham before the public collapse of her marriage with Prince Charles (Jack Farthing, 'The Lost Daughter'). They are three days of torture for Diana, her grasp on herself swiftly coming undone under the ever-present watchful eye of the Royals and their staff, headed by Major Alistar Gregory (Timothy Spall, 'Mr Turner'). With the now-abandoned Spencer family estate of her childhood within sight, Diana is pulled between the woman she was, the woman she is expected to be and the woman she longs to be, the stakes of which are her very sanity.

By freeing the film from the need to adhere to history, Larraín and screenwriter Stephen Knight take the opportunity to construct 'Spencer' as a psychologically-driven work rather than one driven by narrative. Through their collective vision, Sandringham House becomes a horrifying labyrinth, a dizzying hall of mirrors Diana is barely able to escape. It means the reality of the film is able to crack open, for her intense pain and frustration to pour forth as a kind of gothic nightmare where we watch the full-fledged attack on Diana's soul and her own devastating destruction of her own body. 'Spencer' doesn't hold back its punches when dealing with Diana's mental health, her bulimia and her self-harm, but it does so without theatrics or drama. "Fable" gives the film permission to be daring, abstract and imaginative, but it maintains the foundation of tragedy, that what we are witnessing is a human being deconstructed and reconstructed before our eyes.

SWITCH: 'SPENCER' TEASER TRAILER

It's difficult not to think of 'Spencer' in relation to 'Jackie'. This is understandable - by the nature of their subjects, the films are perfect companions to one another: portraits of women in a state of collapse within the absurd circus of public life. They're also both films just as concerned with iconography as with reality, how the public perception of these women shape our understanding of them. Where Jackie Kennedy's triumph is her power to construct that icon herself, the tragedy for Diana in 'Spencer' is witnessing her wrestle with the icon being thrust upon her, one of tradition, status and expectation that does not fit who she really is. Where 'Jackie' is a front-row seat at the act of construction, a careful and considered film on the nature of control, 'Spencer' is messier, more defiant, more unwieldy, a film about the nature of being controlled. This isn't to say that Larraín doesn't exhibit the same level of specificity here that made 'Jackie' so sublime, but in 'Spencer' those skills are employed to a different end. The melodrama and theatricality are even more heightened, Knight's screenplay almost functioning as an internal monologue from Diana spoken and expressed directly into Claire Mathon's camera, shockingly intimate and unrelenting. We're not seeing Diana's breakdown as an observer, the way we viewed Jackie's grief. We're seeing Diana's breakdown through Diana's eyes, driven and distorted by her intense pain, paranoia and fury, a soul ready to collapse.

As such, the Diana in 'Spencer' very much positions herself as the centre of this melodrama or this opera, the central tragic figure in this hellish existence. The traditions she must adhere to become all the more absurd, the more archaic and the more bizarre, with their effect on her all the more potent and intense. The Royals are not humans but mostly silent monuments, disapproving eyes staring across tables and through windows, almost from within the wooden panels of the walls of Sandringham House itself. There's a palpable, crushing sense of claustrophobia in 'Spencer', like the air itself is closing in around her. It really is impossible for us to imagine the intense loneliness of her existence in such a place, where every aspect of life must adhere to planning and schedule, where your every move is observed and debated and scrutinised. Diana walks the most lavish of halls, wears the most beautiful clothes, eats the finest foods, but all within a place that is cold and distant and ancient. As she says at one point, in this world, the past and the present are the same. She is a creature of the future though, and how can a creature of the future be expected to survive in such a place?

In many ways, 'Spencer' is an even more daring film than 'Jackie', taking wilder swings and asking much more of its audience. Thank goodness then for the exacting, passionate hands of Pablo Larraín, who fashions it into a magnificent dreamscape, somewhere between a dazzling chamber opera, a disorienting nightmare and a lavish melodrama. Of course everything is heightened to the heavens; we've stepped through the looking glass into the kind of world none of us could hope to see let alone understand, where the most bizarre rituals exist because tradition dictates that they must. Larraín is a master with the extremes of human emotion, and he wields this skill with breathtaking opulence. This sensibility is married so beautifully with cinematographer Claire Mathon ('Portrait of a Lady on Fire'), shooting with 16mm to give a sense of peeking through the curtains of time, but with a ferocious immediacy that cuts to the heart of Diana like a knife. Equally vital is Jonny Greenwood's astounding score, a dizzying and disorienting gothic marvel akin to his work with Paul. Thomas Anderson. Larraín is not giving us some sweeping emotional drama or some tidy biopic with 'Spencer', but a rhapsody of a soul fighting to survive, filtered through our own understanding and relationship with the iconography of Princess Diana. This is only achievable in symbiosis with his creative team - not just Mathon and Greenwood, but others such as editor Sebastián Sepúlveda, production designer Guy Hendrix Dyas and costume designer Jacqueline Durran. The vision is singular because those constructing it understand the story they are telling.

This is also vital to the success of Kristen Stewart's performance as Diana. The film rests so much on her shoulders, and what Larraín and Knight ask of her is enormous. It's one thing to capture a woman in such a state of crisis, but quite another when that woman is one of the most famous of the last 50 years, whose face and voice are imprinted on the memories of millions. The triumph of Stewart's performance is that, just as Natalie Portman did with 'Jackie', she understands the importance of that iconography to the story being told. It is a veneer, a facade, a lens through which we can view this woman, but the facade does not necessarily match the woman within. Stewart's performance is fearless, specific, compassionate, unrelenting, furious, scattered and breathtaking, a portrait of Diana uninterested in mimicry and invested in truth. This extends to her petulance, understandable in the situation she is in. Diana is in freefall for most of the film, desperately trying to catch anything that will save her, and Stewart's Diana is a trapped animal unafraid to hurt if it will guarantee her safety. Stewart always felt like an inspired choice for this role, and that faith is more than justified in its remarkable execution.

For the most part, the primary supporting cast for Diana occupy not members of the Royal Family, but their staff. Some of them become touchstones for her, such as her dresser Maggie, played so compassionately by Sally Hawkins ('The Shape Of Water'), or the Royal Head Chef Darren McGrady, a beautifully gentle performance from Sean Harris ('Mission: Impossible - Fallout'). By comparison, Timothy Spall imbues Major Gregory with the full weight of the institution of the monarchy, the shadow always close behind Diana, scrutinising her every action. It's to Spall's credit as the great actor he is that Major Gregory is never a villain, not without a sense of compassion or patience, but still a man whose whole being is in service to the idea of the Crown.

Credit must also be given to the brilliant work from Jack Nielen as William and Freddie Spry as Harry. Many of the most moving scenes in 'Spencer' see Diana with her sons, and perhaps the greatest element of tragedy in the film is the degree to which William takes it upon himself to protect his crumbling mother. 'Spencer' asks a lot of these two young actors, and they rise so beautifully to the challenge.

For the first half an hour of 'Spencer', I found myself slightly baffled by it. There was an opulence, a melodrama to it even more so than I had expected, and I could hear the gears in my head having to realign to match with it. At no point though did I resent this, so surprised and exhilarated was I by what I was seeing. I went into 'Spencer' with enormous expectations, and it not only met them, but surpassed them and then completely sideswiped them. This is an extraordinary film, singular and unrelenting in its vision, magnificently strange, beautifully haunting and deeply moving. It's as if we have chanced upon the ghost of Diana herself, wandering the halls of Sandringham House, isolated and trapped and desperate to escape. I found myself gasping with delight at the audacity of it, the daring, the fury, the passion. Pablo Larraín has delivered us a beguiling cinematic treasure, with a career-defining performance from Kristen Stewart that will be discussed for years to come. I would not be surprised if, in 12 months time, 'Spencer' is still sitting high on my list as one of my favourite films of the year.