To shoot UNSANE, Steven Soderbergh used three iPhone 7 Plus phones, with three Moment lenses (18mm, 60mm, a fisheye) and the $15 FiLMiC Pro app. “I think this is the future,” he said.

Fresh off her triumphant turn as Queen Elizabeth II in "The Crown," Claire Foy is about to take cinema by storm. This fall Foy will star in Damien Chazelle's "First Man," and she is also set to play Lisbeth Salander in "The Girl in the Spider's Web." In the meantime, she stars in the Steven Soderbergh-helmed iPhone movie "Unsane." That's right, Soderbergh shot his psychological thriller on an iPhone, Sean Baker-Style. The film has Foy's Sawyer Valentin involuntarily committed into an insane asylum, she seems to think it's a mistake and pleads for her case, to no avail. Soderbergh, un-retired last year with the light, entertaining "Logan Lucky," has this latest endeavor taking him on a darker path.

The movie “Unsane” most resembles in terms of story is obviously Sam Fuller’s “Shock Corridor.” However, everything else about the newly un-retired writer-director’s latest film feels modern and of its era. Foy's Valentin, God I love this actress, plays a smart, highly successful, blunt-speaking data analyst whose mounting paranoia about being stalked by a family friend has had her on edge for years.

Hell, she's even moved to Pennsvlvania from Boston, but he finds her there. She refuses to tell her mom (as played by Amy Irving) about the creep, but soon finds counseling at the Highland Creek Behavioral Center, where, in what should have been a healthy vent of bottled frustrations, she admits to having had suicidal thoughts. She involuntarily signs her way to being committed for 24 hours, which is then extended for a week when her violent protests make deem her too mentally fragile to reenter society. And so, Sawyer's fight against this repressive system, which has the psychiatric hospital holding patients until their health insurance runs out, welcome to America, is filled with beautifully developed hallway shots and an eerie uncompromising claustrophobia that holds the viewer to a grip for its first 70 minutes. 

It doesn't help that a violent patient (Juno Temple) has taken a disliking to Valentin inside the facility, but our heroine does find comfort in smooth-as-ice Nate (Jay Pharoah), a patient that clearly knows a thing or two about the corrupt system he's been framed in. Every scene Pharoah's in shimmers with energy, known for a 7 year stint on SNL between 2010 and 2016, the actor's chemistry with Foy here is palpable and almost, dare I say it, erotic. 

Things get tense when Valentin soon realizes that male nurse George is actually her stalker David Strine (Joshua Leonard). She tells the doctors and nurses there, but they don't believe her, they just think she's a loon and send her down to solitary confinement after she punches George.

The "Shock Corridor" comparisons have to do with the fairly pulpy, claustrophobic story of institutional oppression. Just like Sam Fuller's classic, this is a messy, unnerving, sometime shocking, psychological affair. 

The screenplay by James Greer and Jonathan Bernstein isn't anything special, it encompasses familiar genre tropes that will not make this a Soderbergh essential by any stretch of the imagination. The film does fly off the rails in its last 20 or so minutes, but it's Foy and Soderbergh that carry it down to the finish line with the kind of director/actress partnership that's all too rare these days.

Soderbergh is once again his director of photography here under pseudonym Peter Andrews, (and as his own editor, using the pseudonym Mary Ann Bernard), and he really does serve us a masterclass of how to use the iphone camera in ways we never thought were possible with such limited tech range.

To shoot Unsane, Soderbergh used three iPhone 7+ phones, he outfitted them with three Moment lenses (18mm, 60mm, and a fisheye). On occasions, he used the phone’s standard lens, and it some scenes it shows but it never distracts or prevents us from being gripped by the film.  The 4K resolution of the iPhone used is actually fairly close to a film camera as Inverse says "in all its 4,000 glorious, horizontal pixels that there’s no difference on the big screen." That's why people watching this film and not knowing it was shot on an iPhone wouldn't tell the difference. This is groundbreaking stuff and almost makes you want to go and make your own movie, it just feels so effortless and easy in how "Unsane" is delivered.

Inverse had this to say about the film’s technology: “To record these intimate, sometimes distorted scenes, Soderbergh used the $15 video app FiLMiC Pro, also used by Baker to shoot Tangerine. Soderbergh also used the $10 FiLMiC Remote app, which allowed him to view the video being shot from one phone on a different phone, if the shooting phone was positioned so that the screen wasn’t easily viewable (like if it was on the floor). “We have seen pictures in articles showing him shooting with FiLMiC Pro, and this is one of the highpoints in the journey of our company,” Neill Barham, CEO of the Seattle-based FiLMiC, tells Inverse, adding that the app has “seen exponential growth in the last few years as the mobile filmmaking trend has exploded.”

“I think this is the future,” Soderbergh said at the Sundance Film Festival in January. “Anybody going to see [Unsane] who has no idea of the backstory to the production will have no idea this was shot on the phone. That’s not part of the conceit.”