Indie game film adaptation Iron Lung earns $21.5 million on opening weekend

A low-budget horror film based on indie game Iron Lung earned $21.5 million on its opening weekend, thanks to the involvement of YouTuber Mark Fischbach, better known as Markiplier. Its success, off a reported production budget of $3 million, points to the significant transmedia potential of even smaller game adaptations.

Iron Lung, based on the 2022 game of the same name, was written, directed by and starred Fischbach, who previously played it for his audience of 38.2 million subscribers on YouTube. It received only a limited international release, and earned $17.8 of its weekend take in the US, where it arrived at #2 on the domestic charts behind Sam Raimi horror Send Help.

The film, like the game, follows the pilot of a decaying submarine navigating an ocean of blood, on a distant moon following the downfall of humanity. The game was developed and published by David Szymanski, and released on Steam in 2022 where it has sold an estimated 310,000 copies according to GameDiscoverCo data. It was subsequently released on Switch and PS5.

Fischbach was an early evangelist for the title and started working on the film in 2023, completing filming in 2024.

The film’s haul falls some way short of the Five Nights At Freddy’s movie, which mustered $80 million for its opening weekend, but its reported budget was much lower and Five Nights at Freddy’s had a much larger audience, with sales in the millions.

A series of other horror films based on indie games are currently in development, including Dredge and Poppy Playtime. Earlier today Mob Entertainment’s George Krstic told GamesIndustry.biz that studio Legendary were “amazing partners” for the latter. “They really understand the IP, they really care. And it’s kind of unique, at least in my experience, that you have partners who are shoulder to shoulder with you on an IP.”