Persona begins with a series of unrelated, sometimes startling, sometimes disturbing images. It’s leader on the film reel, and it establishes the film’s narrative distance. We’re not just removed from the action; the action’s on display at multiple levels, including one involving a young boy, played by Jörgen Lindström, who provides bookends for the film.

He’s star Liv Ullmann’s son, but he’s never identified as such. Instead, he’s just the one with the most vested interest at the level.

Ullmann plays a famous theater and film actor who, all of a sudden, stops talking one night during a performance. It only lasts a minute, but the next day, she’s not talking at all, and she isn’t moving around either. She’s stopped expressing herself in any way, which lands her in the hospital, where she gets a full-time nurse to look after her. Bibi Andersson plays the nurse.

According to the doctor (a fantastic Margaretha Krook), Ullmann has nothing physically or mentally (though, sixties mentally) wrong. Andersson is patient and kind, trying to bond with Ullmann, who does react at times—like when Andersson starts reading her a letter from her husband—but there’s not much change.

The audience knows Ullmann is moving and reactive; we watch her watch Vietnam War news coverage in the middle of the night, recoiling in horror at the reality she finds herself in. The war footage calls back to the opening imagery; Ullmann’s experiencing and shutting herself away from the miserable world around her.

With no change as far as the medical staff can see, Krook decides it’d be best for Ullmann and Andersson to head out to her vacation house. Krook thinks she knows what’s going on with Ullmann; she’s just let the disconnect between apathy and empathy break her, and now she’s working through it, researching like an actor. The scene—Krook’s final one in the film and absolutely phenomenal—sets up two recurring themes. First, someone projecting their assumptions of Ullmann’s thoughts and feelings on a silent Ullmann. Second, the acting a part bit.

With the minor exceptions of the opening leader montage, the finale, and an act break—with the film “burning” to remind us we’re not on holiday with Ullmann and Andersson, we’re watching them far removed–Persona has a relatively standard epical arc with Andersson as the protagonist.

She gets this strange but not necessarily unpleasant assignment—Andersson goes into it assuming Ullmann wants to play a mind game with her companion, something Krook dissuades but informs Andersson later on—which turns into an extended holiday out at the beach. Andersson and Ullmann become pals, drinking wine, sunbathing, reading books, writing letters. It’s a holiday. Only Andersson does all the talking, though Ullmann does respond non-verbally to questions. So her condition’s changed a little, in relative line with Krook’s parting diagnosis.

Things change for the pair when Andersson gets super drunk and shares a very personal memory with Ullmann. Andersson becomes convinced Ullmann speaks to her briefly, then comes to visit her in the middle of the night. The next day, Ullmann’s again not talking and denies either event. Must’ve been drunk dreams.

When Andersson’s heading into town the next time for supplies, she takes the outgoing mail, including a letter from Ullmann to the doctor. Andersson can’t help but read the contents, which mainly concern her, with Ullmann making some very callous, mercenary observations. From then on, Andersson doesn’t think she can trust Ullmann but also finds herself becoming more and more wrapped in Ullmann’s “performance.” She just does it knowingly and often hatefully.

The film doesn’t show Ullmann speaking to Andersson when Andersson thinks she is speaking to her. It doesn’t expressively determine whether the middle-of-the-night visit is actual or dream. But it clearly shows Ullmann hurrying to finish the letter and leaving it unsealed for Andersson to take. Persona’s got all sorts of mysteries to it, but Ullmann’s never not an enigma. We get the two private moments with her, the Vietnam footage, then her looking at a photo from World War II showing the Nazis terrorizing civilians. The horror of the world is very much on Ullmann’s mind. But is it on her mind for actor’s fodder, or what’s underneath it?

Andersson becomes convinced Ullmann’s using her as an avatar: it’s not Andersson projecting on the unspeaking Ullmann; it’s Ullmann doing it the other way. Except, of course, it’d be a reflection of that projection, which leads to some fascinating scenes and performances. From the start—in no small part thanks to the opening sequence—Persona seems ready to submerge itself in the surreal, but Andersson and Ullmann’s performances are always firmly grounded. The confusion and hurt are always genuine.

Director Bergman’s got some phenomenal sequences, both directing and in the script. The script’s deliberate in presenting the pair’s evolving relationship, which scenes it shows, which it skips. The direction’s all about the performances, down to a sequence where we literally get to see it from each character’s perspective.

There are numerous second-half plot reveals—mostly about Ullmann’s husband, Gunnar Björnstrand, and son Lindström–and they’re perfect for deepening the existing character drama. At times, Persona is a character study; at times, it’s a psychological thriller; it’s always mesmerizing.

Whether Andersson or Ullmann’s better is probably a matter of personal preference and, of course, what a viewer’s projecting on the character and its actor. It’s a perpetually fascinating film.

Great black and white photography from Sven Nykvist, editing from Ulla Ryghe, music from Lars Johan Werle. Bibi Lindström’s production design is the third star after Ullmann and Andersson. Mago’s costumes are probably fourth.

Persona is an exhilarating, singular experience.