Few films have given us as many uninterrupted opportunities to ponder the singular, unique presence of Kristen Stewart as Olivier Assayas’s Personal Shopper. She is, it could be argued, the only real character of significance in it, front and center of every scene, many of them played against no other actors. And even in those circumstances, she still makes us come to her. Most actors aren’t willing to underplay as unapologetically as she does – it either doesn’t even occur to them, or it’s deemed too risky. So they put themselves out to us, some in explicit ways (by playing heroes, by getting laughs, by charming us with their good looks and charisma), some less so (by dazzling us with their craft, with the intensity of their work, with the depth of their disappearance into character).

Stewart doesn’t do that; she plays quiet introverts, barely raises her voice, makes her effects subtle and tiny, and plays with such authenticity that for a good long while, more than a few less perceptive souls deemed her a Bad Actress. She’s not – she’s always right there in the moment. But she’s not needy in the ways we so often ask our movie stars to be. Most of our actors, and this shouldn’t be taken pejoratively, are like dogs; they bound around for us, and seem to thrive on our applause and affection. Kristen Stewart, on the other hand, is a cat. She’s not working for your love. She knows you’ll come around.

(Jason Bailey / Flavorwire)

That aloofness has become, over her past few years of increasingly exciting projects, her most valuable asset as an actor. It’s made her a full-on collaborator according to director Assayas, who cast her in his previous film, Clouds of Sils Maria and has said before that he considers his lead actors to be co-directors, so full is their influence on the work they’re crafting together. “She’s alone a lot of the time, so a lot of the pacing, a lot of the way my shots are designed, are reinterpreted by an actor… it’s an essential part of what this film is about,” he explained at a press conference following the film’s New York Film Festival media screening Thursday. “There’s a lot of scenes or moments that were much shorter or slightly different in my screenplay, and it was really up to Kristen, within the shot, to put the emphasis on this or that. And she dug up, from within the character and the story, whatever resonated with her. I think with another actress, giving a different pace to the shot, it would’ve been a very different film.”

She plays Maureen, a young American living in Paris, mourning the recent death of her twin brother (of a heart attack, caused by a medical condition they share). She works as the personal shopper and de facto gopher of a supermodel – the second time she has played, for Assayas, an employee of the type of famous person she herself is off-screen, so let’s put in a pin in that to discuss on another occasion. She is also a spiritual medium, as was her brother, so she is waiting for him to communicate with her in some way or another. So yes, it’s somehow a cross between Clouds of Sils Maria and The Conjuring, and even more improbably, it works.

(IFC Films)

Assayas is clearly having fun playing in the toolbox of ghost stories, and he makes his special effects tiny but effective, subtly done, lingering on them and letting them haunt us. But he’s also dipping in to the realm of the non-supernatural thriller, in a riveting series of scenes wherein Maureen receives inexplicable text messages, her reaction going from mild annoyance to genuine curiosity to outright distress. The film is patient enough to let this stranger draw her out, wise to the ways that sometimes we can type the kind of things we’re not honest enough to say out loud. The combination of her playing and his execution turn the dullest of human activities into something alternately riveting and frightening.

He turns the movie over to her, and she is more than up to the task. “I was really struck by specific shots that were not supposed to be that long,” Assayas recalled, “but once in a while, Kristen would do something, and I would turn to my continuity girl and ask her, ‘How long was this shot?’ And she would tell me, like, three minutes. And I would just freak out, because I did not realize it was that long, because I was not bored one second. I was discovering something new that Kristen was bringing.”

(Jason Bailey / Flavorwire)

And that’s how the movie becomes something more than a ghost story or a character study. “I think that Maureen wants to be entirely invisible, and at the same time, really seen,” Stewart said of her character. “And she really struggles with that, and I think that’s pretty much everyone, right now. Even the most out-there people, that can’t be 100% true. Like, I don’t have public social media things that I engage with. But I ultimately want to be seen.”

That’s what makes Stewart such a fascinating enigma as a performer. After years of fronting one of the most commercially successful film franchises of our time, and taking the lumps of its critical reception, she was free to do whatever she wanted, and to be whatever kind of actor she wanted to be. So she makes small, sometimes baffling films. She takes on roles that are often purposefully unglamorous, and gives performances that are sometimes astonishing and sometimes impenetrable, and often both. She gives not two shits about how she looks off the red carpet, and even in press conference situation, she doesn’t speak in the kind of pre-packaged sound bytes that most actors do; she wanders, trails off, starts over, and reveals a mind that is constantly reframing its thoughts (Verbatim quote from Thursday’s presser: “We stalk each other. I stalk people. I get stalked. We are all obsessively – y’know what I mean? Um. Uh, so it’s weird. It’s like, um, she’s struggling with a whole identity crisis, because she’s two separate versions of a person, and that’s not a bad thing, it’s just hard to sort of contend with, um, as a, y’know…”). And more than anything, she seems patently disinterested in what the rest of us think of what she’s doing. For an actor of her age, in the Year of our Lord 2016, that’s downright subversive.

Personal Shopper is playing this week at the New York Film Festival. It’s slated for theatrical release, ugh, next spring.