In June 1990, a researcher named Naren Warne from the Async Research Institute becomes separated from his group and vanishes into a parallel dimension known as the Backrooms—a labyrinth of dull yellow rooms, flickering fluorescent lights, endless hallways, and oddly malformed furniture. The footage of his ordeal is recovered and later shown to Async scientists on monitors, hinting at something real yet unknowable beyond ordinary reality.
Clark, a failed architect and the owner of a struggling furniture store, is trying to cope with his alcoholism and a crumbling marriage. [Chiwetel Ejiofor] plays him with quiet weariness, giving weight to a life that seems to circle around unfinished plans and missed chances. He begins sessions with a therapist, Mary Kline, who is portrayed by [Renate Reinsve]. Mary is a professional grappling with her own past—trauma from the demolition of her childhood home and her agoraphobic mother’s institutionalization—and she becomes a counterpoint to Clark’s stubborn fear of facing responsibility. At home and at work, Clark’s world grows increasingly unstable: the store’s nights feel charged with a strange energy, the lights flicker without mercy, and Clark’s television behaves as if it has a will of its own.
Clark’s routine is further destabilized when his assistant manager Kat and her boyfriend Bobby record a television commercial featuring Clark in the store’s pirate mascot costume. The seemingly low-key stunt spirals into a doorway to the extraordinary: one night, after inspecting a mysterious glowing slit in the wall near the breaker box, Clark falls through and lands back in the Backrooms. He finds Naren Warne’s belongings and narrowly escapes back to the store as an unseen entity closes in, with an Async scientist, Phil, watching the whole sequence through a surveillance camera.
Seeking proof, Clark brings Kat and Bobby into the Backrooms to document their discoveries. Bobby ventures down a steep, treacherously tilted corridor and is seized by an unseen force; Clark and Kat chase after him, and the two become separated in a maze of disorienting spaces. Clark moves through increasingly disordered and uncanny environments and is eventually pursued by two humanoid figures that force him into a dead end. He hears Kat calling for him and, in a desperate moment, places the camera down to search for her, only for something to lift the camera away as Kat screams behind him.
Meanwhile, Mary receives a cryptic answering machine message from Clark, who explains that he’s choosing to stay in the Backrooms and will not be returning. Back in the living room, Phil watches a family TV and recognizes Clark in the furniture-store commercial. Driven by concern, Mary goes to the store and steps into the Backrooms herself, drawn by a need to understand what Clark has become and whether there is any chance of help. Inside, she discovers a crude mural with enigmatic text and a presence resembling the one that dragged Bobby away. An apparently unstable Clark arrives, trying to calm Mary before choking her unconscious when he fears the approaching entity.
Mary awakens to find herself tied to a chair in a dining-room-like space, opposite Clark and three motionless, imperfect simulacra of humans. They sit impassively as Clark cuts open the scene with a brutal display—stabbing one figure and revealing they’re made of an edible white substance—before unveiling Kat’s severed head in a refrigerator. Clark demands that Mary continue their therapy sessions, but she confronts him with the truth that his wife left him because he cannot take responsibility for his failures. Just as she starts to free herself, a towering, deformed simulacrum of Clark—dressed as the pirate mascot—arrives. The creature attacks, mortality collides with memory, and Mary is forced to flee through the chaotic, surreal spaces toward a compromised replica of the furniture store. Cornered, she fights back with a chunk of concrete from her childhood, stunning the monster long enough for an Async gas trap to activate. The creature is subdued, and Mary is taken to a research facility for examination.
Recovered and resilient, Mary is placed in an interrogation room where she meets Phil. He explains that Async originally built magnetic resonance imaging machines and, in their pursuit of knowledge, discovered the Backrooms, which have since become their main research focus. When she asks if she can go home, Phil’s response is deliberately noncommittal, suggesting that the decision is not his to make. Inside the Backrooms, the spaces are shaped by Mary’s memories and trauma, culminating in a final, eerily similar interrogation room where a deformed version of Mary sits, still and silent.
This story unfolds with a measured, observational tone that highlights the fragility of ordinary life when confronted with a realm that tests the boundaries of perception, memory, and control. The film weaves together personal crisis, theoretical mystery, and a creeping sense of inevitability as its characters confront what happens when reality itself frays and the line between therapy, science, and nightmare becomes dangerously thin.
