Steven Soderbergh’s second tie-up with Bleecker Street is his horror thriller Unsane, which stars The Crown‘s Claire Foy as a woman involuntarily committed to a mental institution where she is confronted by her greatest fear — but is it real or a delusion? The pic, reportedly shot via iPhone, co-stars Joshua Leonard, Jay Pharoah, Juno Temple, Aimee Mullins and Amy Irving and is having its world premiere at next month’s Berlin Film Festival. It hits theaters March 23.

Jonathan Bernstein & James Greer wrote the screenplay, which sets the stage for what seems to be an all-in turn from Foy, who at first believes she has a stalker but begins to wonder if it’s all in her head. She heads to a mental hospital to get some answers, but is admitted against her will instead.

Unsane is being co-distributed in the U.S. by Soderbergh’s Fingerprint Releasing and Bleecker Street, who teamed on last year’s Logan Lucky. New Regency has international rights on the film in all territories outside the U.S. and is distributing it via 20th Century Fox International.

Check out the trailer above.