Steven Soderbergh, who supposedly “retired” from filmmaking a few years ago, turns out to have done nothing of the sort. He simply is changing things up, and that includes shooting his latest movie, Unsaneon a schedule of less than two weeks using an iPhone. But those who might fear for the quality of this Oscar-winning filmmaker responsible for the likes of Traffic, Erin Brockovich, the Ocean’s trilogy, sex, lies and videotape and so on should rest comfortably: As I say in my video review (click the link above to watch), Unsane is an insanely terrifying psychological thriller.

Soderbergh has made a bone-chilling nail-biter that just might freak you out and have you watching your back. It’s smart, suspenseful and genuinely frightening — all the attributes a story like this needs. Claire Foy is sensational as Sawyer, a young woman who has just moved from Boston to Pennsylvania in order to escape the trauma of being stalked by a guy she met when she was caring for his ailing father. He gets too close for comfort. Generally alone in a new city, she spends much of her time at work or on social media and Facetime but still is haunted by the past experience. She goes to a mental health clinic just to get some counseling but ends up in eerie involuntary confinement for what is supposed to be 24 hours. But, through circumstance and some misbegotten actions on her part, it just gets worse over the course of seven days.

As her ordeal continues in this weird facility, she is befriended by another “patient,” Nate (Jay Pharoah), who has smuggled in a cell phone which she uses to call her mother (Amy Irving) to send out an SOS. Mom arrives to check her daughter out, but things aren’t as easy as they seem. An orderly (Joshua Leonard) turns out to be, you guessed it, her stalker. Or is he? This is one of those movies where you are never quite sure if it’s real or if she is imagining all this bad stuff is really happening to her. I have to say that after a while I wasn’t sure, but I can safely say you might end up screaming at the screen. To give away much more than the basic bones of the plot would be critic malpractice.

Whatever the case, Soderbergh — iPhone or Imax — is smart enough to know it is the content not the device that matters, and he has crafted a nice genre piece. Working from a smart script from Jonathan Bernstein and James Greer, he also has made a film with inadvertent relevance to #MeToo with a main female protagonist longing to be listened to against all odds. Foy expertly navigates the role without ever going over the top.

As usual Soderbergh uses his familiar pseudonyms for tech credits, serving as cinematographer Peter Andrews and editor Mary Ann Bernard, and he proves you actually can phone in a good movie these days. He’s still got it.

Bleecker Street releases the Fingerprint production this Friday. Do you plan to see Unsane? Let us know what you think.