The hidden history of every upcoming online horror movie: From Backrooms 2 to Siren Head

Films like Obsession and Backrooms have changed the way the movie industry views horror, and its box office potential. The real scary bit for the establishment: their back stories are nothing like those of the average blockbuster. Backrooms's is a classic.

In 2019, a photo of an empty, seemingly endless office building was posted anonymously to 4chan. It's a message board best known for its unmoderated forums and countless controversies.

The caption, just 100 or so words long, spoke of limitless hallways, the flicker and hum of fluorescent lights, and unseen entities lurking around countless corners.

The Backrooms is possibly the most successful piece of anonymous literature in human history. The original post inspired thousands, if not millions, of memes and reposts, short stories, fan art, original music, and video games. In 2022, then-17-year-old filmmaker Kane Parsons began a series of CGI shorts that expanded the world and lore of the original post a hundred times over.

A24 recruited Parsons for a feature-length version of Backrooms, which released in 2026 and made a staggering $400 million at the box office. All that from an anonymous post on an anonymous forum. Since the release of Backrooms, major studios have announced acquisitions, directors, and castings for online horror movies.

“It’s felt like a bit of a drought for this sort of adaptation” says online horror artist Eduardo Valdés-Hevia, known to his hundreds of thousands of followers as Valdevia – “Backrooms coming out uncorked the bottle and finally let Hollywood executives start taking risks on cool internet things.”

Who owns the rights to internet fiction isn’t always clear. The SCP Foundation, a collaborative horror writing project, covers all of its output with the Creative Commons license – but this hasn’t stopped production companies from announcing film versions of their own. And it’s even harder with anonymous posts – A24 doesn’t even own the copyright to Backrooms, only Parsons’ interpretation of the original text.

The SCP case in particular has inspired questions about whether major studios are ready to give these pieces of internet fiction the respect they deserve.

With that in mind, I set out to round up every upcoming online horror film, and find out as much as I could about the hidden history behind them. You’ll also find comments from Valdés-Hevia throughout our list.

We'll split this creepy trip into online subculture sections, from creepypasta to SCP and the works of Trevor Henderson. And don't worry if you're not familiar with these — we'll explain everything as we go. Let's start with the sub-genre under the spotlight right now, the YouTuber horror movie...

YOUTUBE HORROR

YouTube has long been the platform of choice for video-based horror series and alternate reality games – massive view counts and meme culture impact make it a top pick for Hollywood execs looking for new IP.

What’s more, the YouTube horror scene has seen online horror auteurs step into the spotlight more often than the writers of early forum posts and creepypasta tales.

“One of the good developments that’s happened in recent years is that the author has been able to stay attached to their own projects,” says Eduardo Valdés-Hevia, “then, when it gets adapted, you get a front-facing person that can stay involved in it.”

Backrooms 2

• Director: Kane Parsons
• Studio: A24

What do you do when your internet horror film makes its budget back 40 times over? Well, you make another one. It’s no surprise A24 has announced a second Backrooms film is on the way, with Kane Parsons at the helm once more (via Deadline).

The first Backrooms film, with its allusions to the shadowy A-Sync corporation and timestamped found footage, ties into the universe Parsons built with his YouTube series – but didn’t cover all of its established lore. The film left out the creepy "organism" monsters Parsons populates his vision of the Backrooms with, as well as much of the history of A-Sync and in-Backrooms locations like the mysterious "red city" seen in a later episode.

All we know about Backrooms 2 is that it’s on the way – there’s no word yet on whether stars Chiwetel Ejiofor and Renate Reinsieve will return for the sequel.

The Mandela Catalogue

• Director: Alex Kirster
• Studio: Amazon MGM, United Artists

YouTuber Alex Kirster created The Mandela Catalogue in 2021, refreshing the analogue horror trend with a mix of VHS aesthetics and pre-internet mystique. The series centres on a fictional county in Wisconsin, which falls under siege by shapeshifting entities called "alternates," and paranormal phenomena.

Amazon MGM, United Artists, and Steven Spielberg’s production company Amblin have teamed up to adapt Kirster’s series into feature-length form (via Deadline). Spielberg’s involvement could point to a sci-fi adaptation in the style of Close Encounters, but the studios have shared no plot details as of yet. It’s due to arrive in theaters on 9th June, 2028.

Portrait of God

• Director: Dylan Clark
• Studio: Lionsgate

Dylan Clark’s Portrait of God has risen to become one of the most celebrated short films in the YouTube horror scene. The original short, uploaded in 2022, depicts a schoolgirl practicing a presentation about a painting of the same name, which slowly reveals a supernatural secret.

Lionsgate announced a feature-length version of Portrait of God in December 2025, long before Backrooms blew up the box office. The studio has called in the big guns for the film’s cast and crew, with Chase Infiniti (One Battle After Another, The Testaments) set to star and Jordan Peele (Get Out, Nope) and Sam Raimi (Spiderman, Evil Dead) teaming up to produce.

SCP FOUNDATION

The SCP Foundation is a fictional international agency that Secures, Contains and Protects anomalous items and entities. Since 2007 its official wiki has compiled around 10,000 mainline entries and thousands of spin-off tales. It’s likely one of the largest fictional universes ever conceived.

The SCP universe has made its way into plenty of games and fan films, but bringing it to the silver screen is complicated by the site’s cast of anonymous authors and the fact all SCP material is released under the Creative Commons Sharealike-Attribution 3.0 license.

I caught up with two SCP Foundation admins, DrEverettMann* and Yossipossi, to talk about how the community feels about two incoming SCP film adaptations.

*(DrEverettMann is a username, not a title)

V/H/S: SCP

• Studio: Spooky Pictures, A24

Horror anthology series V/H/S seems a perfect fit for an SCP Foundation film – a collection of shorts would give V/H/S owner Spooky Pictures and collaborator A24 an opportunity to show off plenty of the site’s iconic monsters and oddities.

Unfortunately, the project seems to have hit choppy waters before it has even set sail. SCP International, the organisation that represents all branches of the SCP Foundation project, released a joint statement claiming staff were not contacted or consulted before Spooky Pictures and A24 announced their film adaptation, though Spooky Pictures did eventually get in touch with the admin team.

SCP wiki admin DrEverettMann tells me seeing the news break was “both exciting and mildly infuriating”, adding that he personally thinks “an SCP movie would be very cool, but we also want to make sure that everybody’s rights are being respected.”

The creative commons license means that SCP Foundation admins and authors don’t need to be informed before its work is adapted, but there are some rules to follow. As the statement says, “A24 does not and cannot have any exclusive rights to anything related to the SCP Foundation, including any films that Spooky Pictures or anyone else may choose to create”.

“The biggest part of this is that they need to attribute the original author of whatever works they’re adapting,” DrEverettMann tells me.

“They need to link back to it and release it under the same license, which means other people can remix or redistribute it as they see fit.”

Yossipossi added that they and the SCP staff hope to “get this entire situation resolved very amicably and peacefully, and we look forward to whatever they produce – assuming it follows the license!”

Untitled NEON SCP Movie

• Studio: NEON

On the other side of the coin, American independent film studio NEON is also working on a film set in the SCP universe. NEON’s project has been acknowledged by SCP Foundation staff in a standalone statement, which credits the firm’s communication and understanding of the Creative Commons license.

The SCP community is fiercely defensive of its Creative Commons status. The staff previously faced down a copyright dispute from Russian writer Andrey Duskin beginning in 2019 (though the matter was actually settled by Russian courts in 2021). Even if Spooky Pictures and A24’s SCP movie is totally legally compliant, NEON’s competing anthology could capture more goodwill from the Foundation’s enormous fanbase thanks to the studio’s open communication.

SCP Wiki admin Yossipossi tells me that they prefer adaptations of their own SCP work to stay true to source where possible: “Keeping the themes at the core message of the original piece is very important to me personally. One of my larger pieces is very thematic, and a lot of its messaging hasn’t always been adapted well by YouTubers.”

Yossipossi also tells me that while SCP works are free to adapt, the site maintains a community and curatorial standards that set it apart from other online horror sources:

“It’s a space that curates its literature, but at the same time isn’t overly critical, and doesn’t have a high bar for entry… I think the SCP wiki fills that niche very well, and that’s why people flock to our site,” says Yossipossi.

TREVOR HENDERSON

Horror artist Trevor Henderson has seen his sketches and artworks of otherworldly animals and humanoids transformed into memes, games, and fan-made films – now, his creations are on their way to feature-length releases.

With almost a million Instagram followers, Henderson is a leading figure in the online horror community. Eduardo Valdés-Hevia tells me he’s “really excited for Trevor’s projects – he’s a personal friend, so I was happy for these adaptations to finally come through. [Our community] came together during the pandemic as a bunch of weird horror internet creators. Eventually we all met in person – it’s been really positive.”

Let's take a closer look at two of the top Trevor Henderson creations currently in production as major movies.

Siren Head

• Director: Zach Cregger
• Studio: Warner Bros.

Henderson’s best known creation is Siren Head, an emaciated giant with a siren for a head. On the surface, that sounds more silly than scary, but Siren Head has become one of the most enduring figures of internet horror’s social media era. As a huge, loud and distinctive creation, Siren Head is easy to recognise during even the fastest doomscrolling sessions.

Like most of the entries on this list, there isn’t a great deal of official info on Siren Head – Valdés-Hevia tells me it’s more like adapting a folk story than a novel. Its original caption states the creature was first seen among telephone poles in the deserts of Arizona, and fan theories suggest that it may have adapted over time to mimic human infrastructure as a form of camouflage.

Warner Bros. has brought on Zach Cregger, Director of Weapons and the recent Resident Evil reboot, to helm the project (via Complex).

Cartoon Cat

• Studio: Sony TriStar

Another Trevor Henderson creation, Cartoon Cat, is being adapted into a feature film by TriStar, a subsidiary of Sony Entertainment. This malicious creature takes the form of a classic animated cat as a way to reflect human nostalgia and collective consciousness, and gain access to the physical plane. According to the Trevor Henderson wiki, Cartoon Cat ranks as one of the most dangerous and malicious of Henderson’s many creature creations.

The development of the Cartoon Cat adaptation was announced within weeks of Siren Head, but the two films are being developed by separate studios. This reflects Henderson’s prolific status within the online horror community, as well as Hollywood’s appetite for these trending creations.

CLASSIC CREEPYPASTA

Creepypasta – a portmanteau of "creepy" and "copy paste" – refers to an early style of online horror writing that circulated in email chains and anonymous forums in the early 2000s. It has become one of the internet’s most enduring native genres, with sites and subreddits like r/nosleep offering modern users the ability to search through the latest and greatest amateur horror fiction.

Many creepypasta legends spring from just a few paragraphs or a piece of edited artwork.

“Some of the best internet horror happened where it was just an initial seed, that gives people just enough for their imaginations to cling onto and expand,” Eduardo Valdés-Hevia tells me. “One maxim I have with horror – the less you know the better.”

“An adaptation of my work would be a little weird,” he continues, “because for the most part, they’re not fully written stories – maybe it’s a world building thing. You’d need to bring in teams of writers to take this world-building and put a story into it.”

The Third Parent

• Director: David Michaels
• Studio: Bleecker Street

The Third Parent is an online horror project that predates the release of Backrooms, but the two films share a similar origin. Rob Lowe will star in this domestic horror drama, based on the story Tommy Taffy by r/nosleep author Elias Witherow, with the film set to release on January 22 2027. Third Parent is the only film on this list with a confirmed 2027 release date, and producers Bleecker Street supposedly used the 2025 Cannes Film Festival to shop the distribution rights to major studios.

I’ve read the original Tommy Taffy post, and I wouldn’t recommend it for those with a weak stomach. Without spoiling anything it’s an extraordinarily violent and disturbing story that would really test any age ratings board if adapted faithfully. I’m expecting The Third Parent to be a slightly milder version.

Jeff the Killer

• Director: Savanah Moss
• Studio: Tongal

Jeff the Killer wasn’t the first creepypasta, but it’s considered by many to be the foundational text of the online horror genre. Unfortunately, it’s pretty crap – a melodramatic and poorly-written story that basically rips off Carrie, kept afloat in the online zeitgeist by an accompanying mega-viral photo and the admittedly spooky catchphrase "Go to Sleep."

Still, the underlying narrative of Jeff the Killer – a disfigured bullying victim taking bloody revenge on his aggressors – is certainly salvageable. TikTok star Savannah Moss has stepped up to translate this cult classic for full-length release (via PHANTASMAG). By the looks of the crowd-sourcing campaign for the film’s poster, this could be a lower-budget affair than some of the major studio titles on this list.

Untitled ‘Missing Girl’ Movie

• Director: TBC
• Studio: Fifty-Fifty Films, Vertigo, Underground

Sydney Sweeney (Euphoria, The Housemaid) is set to produce and star in an adaptation of r/nosleep story "I pretended to be a missing girl" via her production company Fifty-Fifty Films (via Bloody Disgusting). The story follows a burglar who assumes the identity of a doppelganger who went missing years prior, so that she can rob a family home – only to realise that she may be the one in danger.

r/nosleep is considered the premier location for short horror writing on Reddit, and many of the stories posted there have been picked up for adaptation. The 2024 TV series Tales from the Void adapted six r/nosleep stories into individual episodes, and studios like Netflix, Sony, and Amazon have secured or optioned the rights to other tales.

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