A furniture-store owner opens a door in his basement and steps into a room he has never seen: fluorescent tubes humming overhead, damp yellow carpet underfoot, walls the color of old paper, and no exit in any direction that ever ends. This is the premise of Backrooms, and the uncanny thing about watching it is that millions of people had already stood in that room before Chiwetel Ejiofor ever walked into it. They had been there on their laptops, at night, alone.

Kane Parsons built Backrooms out of a myth he did not invent and does not own. The Backrooms began as a single anonymous photograph posted to an image board in 2019 — an empty office floor, wrong in a way no one could quite name — and grew into a sprawl of found-footage videos on YouTube, several of them made by Parsons himself while he was still a teenager. It became, almost by accident, the first horror universe authored collectively by the internet rather than by a studio or a novelist. That Parsons, now twenty, adapted his own web series into A24‘s highest-grossing film is a career origin cinema has not seen before. He is the youngest director to open a film at number one at both the domestic and the global box office.

The film keeps the source’s central rule intact, and everything else follows from it. The Backrooms are not a monster with a lair. They are an architecture that behaves like a predator. Clark, a failed architect who now sells sofas, finds the portal and escapes, then tells his therapist, Mary Kline, what he saw. When he goes back in and does not return, Mary goes after him. The dread the trailer promises is spatial and administrative — corridors that repeat, light that never dims, time that quietly drains — rather than the choreography of chase and kill that most studio horror is built on.

That is why the property belongs to the analog-dread lineage rather than to the jump-scare tradition. Backrooms sits with Cube, with the impossible expanding house of Mark Danielewski’s House of Leaves, with The Blair Witch Project, and with Skinamarink — works where the fear is the plausibility of the format and the wrongness of ordinary space, not a creature unveiled in the third act. Parsons’ contribution was to locate that dread in the most banal environment imaginable: the vacant office floor, the fluorescent corridor, the transitional place you pass through every day and never once look at.

The Room That Refuses to Change

There is a structural argument underneath the film, and it is the opposite of how horror usually works. A conventional horror film escalates — more threat, faster cuts, tighter spaces. The Backrooms do the reverse. Sameness is the threat. The room does not change, and its refusal to change is what wears a person down. The source’s grammar, visible in the web series and carried into the trailer, is repetition without progress: the same yellow, the same hum, the same corner arriving again. The horror is not being chased. It is being unable to tell whether you are still moving.

Parsons reaches that feeling by subtraction. He strips the genre of its customary instruments — darkness, shadow, silence — and forces the dread to come from their opposites: over-illumination and monotony. The palette is a single sick yellow. The light is flat and frontal and never lets up. In place of a score that stabs, there is an ambient hum, which Parsons kept under his own control by co-scoring the film himself. It is an unusually disciplined idea for a first feature, and it is the clearest evidence that the director understands exactly why his source frightened people: not because something jumped out, but because nothing did, for far too long.

Two Faces in an Empty Place

A feature needs what a three-minute clip never did — a person for the dread to happen to. Backrooms answers with two.

Ejiofor gives Clark the specific weariness of a man who trained to build things and ended up maintaining a shop; the failed architect wandering an infinite floorplan is the film’s cruelest joke and its quietest tragedy. Renate Reinsve, the Norwegian actor who broke through in Joachim Trier’s The Worst Person in the World, grounds the second half. Her Mary Kline is a therapist — a professional whose entire craft is talking people back from the edge — walking into a place engineered to erase the difference between searching and giving up. The casting is an argument in itself: put the one character whose job is to help people find their way out into the one space with no way out.

Around them the population stays deliberately thin. Mark Duplass, Finn Bennett, and Lukita Maxwell fill a small ensemble in a film that understands crowds would ruin it; the Backrooms are frightening because they are empty, and every additional face is a concession to comfort the story mostly refuses. Will Soodik wrote the screenplay. The whole apparatus — A24 as distributor, with 21 Laps, Atomic Monster, North Road and others behind it — is pointed at preserving the sensation of a place that should not be able to hold you, and does.

An Image Born Free, Now an Asset

There is an argument buried in where Backrooms is arriving, and it is worth stating plainly. A24 released the film to theaters and it became a phenomenon, grossing close to four hundred million dollars against a ten-million-dollar budget and drawing some of the strongest reviews of the studio’s year. But the Backrooms were never a theatrical object by nature. They were made to be watched on a small screen, in private, at the hour when a corridor of fluorescent light looks exactly like the hallway outside your own bedroom.

The move to HBO Max, then, is not a step down from the big screen. It is the myth returning to the conditions that produced it — the solitary, late-night, laptop-lit viewing that turned a photograph of an empty room into something a generation could not stop thinking about. It also completes a circuit the film has been running since 2019. An image that belonged to no one, built by everyone, became studio property, became A24’s biggest hit, and now becomes a subscriber-retention asset inside the Warner Bros. Discovery machine. The internet no longer competes with Hollywood for its myths. It incubates them, and Hollywood harvests them.

What none of this settles — and what a premiere should not pretend to settle — is the film’s actual subject. The Backrooms keep you because some part of you agrees to stop looking for the door. Whether the people who go in come back the same is the question Parsons builds the film around, and it is the same question the format has always posed to whoever is watching alone in the small hours: how long before you stop searching for the exit and simply begin to live in the room. The exit may be findable. The person who finally uses it may not be entirely recoverable.

Backrooms begins streaming on HBO Max on September 25, 2026, and airs on HBO the following night, Saturday, September 26, at 8:00 p.m. ET. The film runs 110 minutes and reached theaters through A24 in May.