According to Variety, the film has set September 25 as its HBO Max streaming date, following a theatrical run that has made it one of the year’s most successful horror releases.
From YouTube Phenomenon to Theatrical Success
The road to the big screen began with Kane Parsons’ YouTube series, which launched in January 2022 under the Kane Pixels name. Inspired by the internet-born Backrooms mythos, the project quickly attracted attention and eventually led to several studios expressing interest in turning the concept into a feature. The picture was formally announced in 2023, with Parsons directing his first feature.
The finished movie centers on Clark, a furniture store owner and former architect played by Chiwetel Ejiofor, who discovers an impossible passage inside his store. The opening leads into a seemingly endless dimension of liminal spaces, where Clark becomes trapped. When he disappears, his therapist, Dr. Mary Kline, played by Renate Reinsve, eventually enters the strange environment herself. Mark Duplass, Finn Bennett and Lukita Maxwell also star.
‘Backrooms’ arrived in U.S. theaters through A24 on May 29 after premiering earlier that month in Santa Monica. Its theatrical performance quickly exceeded expectations. The title opened with $81.5 million domestically and $118 million worldwide, giving A24 its biggest opening weekend ever.
That momentum continued well beyond opening weekend. The film has now grossed $396.5 million worldwide, making it A24’s highest-grossing picture to date. It also ranks as the second-highest-grossing horror movie of 2026 and has established Parsons as the youngest filmmaker to have a No. 1 at the U.S. box office.
The HBO Max release comes after the hit’s digital debut on July 14, as well as the July release of an extended cut titled “Backrooms: Everything Must Go Edition” which added 15 minutes of footage.