Pablo Larraín’s Spencer is, per the opening text, “a fable from a true tragedy.” This is an ornate (perhaps overly so) way of saying that it is a fictionalized imagining of real events, which feels important to stress these days, lest viewers assume that director Larraín and screenwriter Stephen Knight are crafting something akin to docudrama. It is true that their film is based on real people – namely, Great Britain’s royal family – and that it is set during a real event, the 1991 Christmas weekend, when they gathered at the Queen’s Sandringham Estate and attempted to ignore the obvious splintering of the marriage between Prince Charles and Princess Diana. Spencer, according to the press notes, is “an imagining of what might have happened during those few fateful days.”

This distinction between fact and fantasy is worth underlining not as a mark against the project; quite the contrary, in fact. We are mired in an age of painfully dull and tritely formulaic biopics, filmed Wikipedia pages like Respect and Bohemian Rhapsody and the like, and Larraín is one of the few filmmakers who seems patently disinterested in such rote affairs. Back in 2016, he directed Jackie, which similarly dramatized and fantasized the life of Jacqueline Kennedy Onassis in the days immediately following her husband’s assassination – but nothing before, and nothing after. Snapshot biopics like these (Selma and Lincoln also leap to mind) succeed over their cradle-to-grave counterparts because it’s simply impossible to pack an entire, eventful life into a single film’s running time; it’s better to telescope into a tightly constrained period of particular stress, and extrapolate our impressions of them, as people, from how they conduct themselves at those most dramatic moments.

This is certainly such a moment for Princess Diana, here played with the right combination of fragility and gravitas by Kristen Stewart. The first time we see her, she’s lost, and she’s late. The official convoy of cars has already brought the rest of the royals to this vast country estate on Christmas Eve, but she has decided to drive herself, and that decision, and its inevitable outcome, suggests that this is a woman who seizes every opportunity for a small rebellion that she can. She’s already fraying at the edges when she arrives, only to be met at the door by the dour Equerry Major Alistair Gregory (Timothy Spall), who informs her that she is to be weighed. “No one is above tradition,” he deadpans, noting that all guests are expected to gain three pounds by the weekend’s end to show they’ve made proper merry. But whatever the logic, it does not seem like a good idea to so closely document the weight of someone we soon discover is suffering from bulimia.

And cutting. And hallucinations. And general anxiety. Diana and Charles (Jack Farthing) are a decade into their frayed marriage, and they’re barely on speaking terms; they exchange loaded looks over dinner, and dialogue broadly signals that things are, indeed, coming to an end: “It’s Christmas. Everything waits until after Christmas.” Diana, who is acutely aware of her husband’s various transgressions, is going a bit out of her mind in the meantime; as she rattles around this gigantic middle-of-nowhere mansion (deliberately framed and photographed to recall the Overlook Hotel in The Shining), she’s haunted by the visions and ghosts. Anne Boelyn keeps showing up, and by this point in her life, Diana finds herself envying the woman who only had to lose her own head to get out of the royal family.

Stewart has always been a performer unafraid to risk doing too little, so she was an unlikely but, it’s now clear, ingenious choice for the role; she’s going through such a period of pronounced anguish that the wrong kind of actor would have played the whole thing as overwrought, and ruined it. It’s one of those performances that amounts to an accumulation of the tiniest, most difficult moments, and when you put them all together a full picture becomes clear, like those photo montages that were so popular in the ’90s. At one point, at the end of a deeply uncomfortable encounter during a binge before a purge, Gregory asks her – but it’s not really a request – to do something for him, for probably the third or fourth time in the conversation. And she replies, “Yes. Maybe. No. Depending on lots of things.” What she’s saying and the way she says it is, well, an eternal mood.

Larraín orchestrates the supporting players like a conductor, bringing in soloists for brief spotlight turns (Sally Hawkins and Sean Harris are especially good as keenly sympathetic support staff) before returning to the main theme. And he gets the look of the picture just right; he’s replicating the washed-out, overcast look of British films of the period (it looks like it could’ve been released by HandMade). And, that opening text aside, he doesn’t even hint at what will ultimately become of Diana, much less do anything as crass as dramatize that. Instead, he pays her the courtesy of giving her the happy ‘80s movie ending she deserved.

If Spencer doesn’t quite take flight as Jackie did, perhaps that’s merely a matter of expectation. Jackie was particularly affecting because we’d never seen a biographical drama quite like it, but now we have. However, every film doesn’t have to innovate, and there are far worse things to be than Pablo Larraín’s second-best snapshot biopic.

B+

“Spencer” is in theaters Friday.