You’ve probably been hearing a lot about Backrooms, the product of 20-year-old director Kane Parsons. With origins dating back to a sci-fi horror web series created by Parsons, the film has officially hit theaters, drawing massive audiences into its unsettling, yellow-walled labyrinth. Without spoiling any of the narrative twists, here is a quick look at the cast, the identity of the creature, and the production secrets that brought this viral creepypasta mythology to the big screen.

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Who is in the Cast of A24’s Backrooms Movie?

Backrooms stars Oscar nominee Chiwetel Ejiofor as Clark, a struggling furniture showroom owner and failed architect who accidentally clips through reality into the endless yellow hallways. Joining him is The Worst Person in the World breakout star Renate Reinsve as Dr. Mary Kline, Clark’s dedicated therapist who gets drawn into the investigation after her client disappears. Independent cinema icon Mark Duplass plays Phil, a high-ranking researcher representing the elusive Async Corporation, while rising stars Finn Bennett (True Detective) and Lukita Maxwell (Shrinking) portray Kat and Bobby, the young furniture store employees who help film the initial expeditions into the liminal maze.

Who Plays the Monster and How Was it Filmed?

One of the biggest real-time search spikes surrounds the identity of the terrifying, wire-thin “Lifeform” that stalks the characters through the chevron-wallpapered office spaces. Instead of relying purely on digital CGI, Parsons chose a highly practical approach. The creature is physically portrayed by Robert Bobroczkyi, a real-life 7-foot-7 former basketball player whose staggering height and unique proportions give the monster its uncanny, deeply unsettling movement style. 

By pairing a 20-year-old digital-native visionary with prestige heavyweights like A24 and James Wan’s Atomic Monster, the film proves that viral internet folklore holds immense commercial and artistic weight.

Backrooms is in theaters now.

Featured Photo: A24

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