Claire Foy in Unsane (Bleecker Street)

 Sawyer Valenti (The Crown’s Claire Foy) has recently relocated and started a new life for herself, despite the objections of her mother (Amy Irving) that she needn’t ever have moved away from Boston. Given Sawyer’s brash treatment of her coworkers, as well as her clipped conversation with her mother over Facetime, it’s clear something is off about her life. After she has a violent outburst during a Tinder date, she seeks help by going to a hospital that hosts a support group for the victims of stalkers.

After the initial screening interview, Sawyer is asked to fill out a clipboard full of seemingly innocuous forms, but as it turns out, she just admitted herself for 24-hour observation. This is only the beginning of her problems. A headstrong woman, her fighting against the hospital’s nurses and orderlies only makes matters worse for her as her outbursts give them grounds to justify extending her stay.

Director Steven Soderbergh has always been one to push the envelope with experimental filmmaking. For a few examples, there is his oddball cult classic Schizopolis in 1996, then 2005’s Bubble, which featured non-actors as well as no script, and 2009’s The Girlfriend Experience, with an adult film actress as its lead. Soderbergh and crew shot Unsane in secrecy, using three different iPhone 7 Pluses with special lenses attached and an app that allowed them to go beyond the built-in features of the cameras. The whole camera department fits into one backpack, which may be a bleak outlook for any camera operator reading this.

Going into Unsane knowing that it was shot on iPhones will certainly affect how you view the film. In the first few minutes, it especially looks like it’s being shot on a phone, with framing and movement that seems just a little off from what we’re used to seeing in movies. When Sawyer sits on a park bench to talk to her mom, the low angle looks amateurish, as well as the scenes of her in a bar, as if she were appearing in the background of another patron’s Instagram post. But I think these early moments are just tips of the hat to the discerning members of the audience. Once the story gets into full swing, it looks less and less like an Instagram story and more like a film shot on professional cameras, which is Soderbergh’s way showing us what these babies can do.

Enough about the technical aspects. Does Unsane work as a thriller? Holy crap, yes, it does. Foy turns in a performance that is far removed from the period piece of The Crown, playing a modern and emotionally complicated woman. Sawyer is not your run-of-the-mill heroine. When bad things start happening to her—whether you agree with the hospital’s procedures or not—there’s some naughty voyeurism going on as we see an abrasive person receive some comeuppance from the hospital staff.

Once she’s inside, she is joined by others, some of whom belong in there, some who may also be in the same boat as Sawyer. Jay Pharaoh from Saturday Night Live plays Nate, a patient undergoing opioid rehabilitation who befriends her and seems more out of place than any of the other patients. Violet (a corn-rowed Juno Temple) in the bed next to her and hates Sawyer upon first sight of the snooty professional woman.

Then there are the nameless nurses, doctors, administrators, and clerical staff with the all too familiar glazed look of unconcern we’ve come to associate with the healthcare industry these days. Remember that Sawyer was originally going to the hospital to join a support group for the victims of stalkers? Well, as it turns out, a man who looks like the one who has been stalking her for the past two years is actually working at the hospital as an orderly, only now he’s got a new name. Of course, none of the bureaucrats bat an eyelash when Sawyer tells them this.

As much as I enjoyed Unsane, the only aspect that didn’t work was the casting of Joshua Leonard as George Shaw, the orderly who may or may not be the stalker. I understand the motivation the filmmakers had in veering away from scenery-chewing villainy and instead making George an everyman, but his personality is practically blank. This choice deflates the tension between Sawyer and her accused tormentor. Admittedly this is a stretch, but could it be that Leonard was cast because he starred in 1999’s The Blair Witch Project, which had a similar experimental quality with the actors controlling the cameras? Who knows.

Comparisons will be drawn to Milos Forman’s One Flew over the Cuckoo’s Nest, but I kept being reminded of Michael Crichton’s Coma (1978), which also features a female protagonist going alone against a sinister hospital that clearly has ulterior motives. The only elements even tying Unsane to the modern day are smartphones—Nate has snuck one inside, which he and Sawyer use to keep in contact with the outside world. Just get rid of those devices, though, and this film could have been made in 1975. The plot is timely, and yet the film itself is timeless—which is how a good thriller should be.