Iron Lung, an adaptation of the video game of the same name by David Szymanski, released in theaters around the U.S. on January 30.
It was entirely self-funded by its writer, director, executive producer, and editor Mark Fischbach, more popularly known as Markiplier per his YouTube channel. Fischbach’s main channel has 38 million subscribers and boasts a total of 23 billion views across his entire channel.
The film also stars Caroline Rose Kaplan, Troy Baker, Elsie Lovelock, Elle LaMont, Mick Lauer, David Pettitt, and Seán McLoughlin, otherwise known as Jacksepticeye, a fellow YouTuber and frequent collaborator of Fischbach’s. The film features an original score by Andrew Hulshult, who previously composed for a number of video games, including Dusk, which was developed by Szymanski.
Iron Lung takes place in the far future, after a mysterious apocalypse called the “Quiet Rapture” in which every star and planet in the universe disappeared without explanation. All the humans on those planets are also gone, and only those who were on spaceships or space stations are left. Fischbach’s character, Simon, is a convict sent to explore a moon containing a mysterious ocean of blood. In order to do so he is welded inside a submarine of dubious quality, the titular “Iron Lung.” Simon and the camera remain inside the sub for the entirety of the film, with few exceptions, as the audience follows Simon’s journey through the ocean. The film is R-rated and contains sensitive content, such as a large amount of gore, and features themes of mental health, hallucination, and cosmic horror. For those who may find these themes triggering, or who are under the age of 17, it is advised to carefully consider the decision to watch the film.
Initially, the film was planned to release in 60 independent theaters in the U.S. However, after Fischbach urged his fans to request that their local theaters play the film, that number grew to over 4000 theaters across North America, Europe, and Oceania.
Iron Lung managed to gross over 40 million dollars on a 3 million dollar budget. Its reception from critics was mixed, with many praising the film’s atmosphere but finding the story and plot to be slow and boring. Fans and audiences, meanwhile, were far more generous, oftentimes finding that the slow pace contributed more than it detracted from the final product.
The Iron Lung video game was solo-developed by David Szymanski and released on the online video game retailer Steam on March 10, 2022. Despite being a short, somewhat rudimentary game with virtually no marketing outside of its Steam page and a trailer uploaded to YouTube, the game found a great degree of success. Following in the footsteps of previous indie horror hits like Five Nights at Freddy’s, much of Iron Lung’s success was due to its popularity on YouTube. Of course, Fischbach made a highly successful video on the game, but a number of other YouTubers made viral videos of playing the game such as Jackcepticeye, Power Pak, and Smii7y.
Iron Lung is not Fischbach’s first foray into acting or more traditional media. He previously produced and starred in a series of interactive films hosted on YouTube. Beginning with “A Date with Markiplier” and ending with “In Space with Markiplier,” the films represented one of Fischbach’s earliest ventures into acting. The first live action show not hosted on YouTube starring Fischbach was the psychological horror series “The Edge of Sleep.” The show is an adaptation of the podcast of the same name, in which Fischbach played the same character. It was released on Amazon Prime on October 15, 2024, and moved to Tubi on May 15, 2025. In addition, Fischbach provided the voice for the characters 5.0.5. and “Black Hot/Sexy Black Hat” for the Cartoon Network show Villainous, which began as a short web series but was eventually granted a full season in 2021.
Movies adapted from video games, which previously had a highly negative reputation, have had a renaissance as of late. Films such as Sonic the Hedgehog, The Super Mario Bros. Movie, A Minecraft Movie, and Five Nights at Freddy’s have experienced a high degree of financial success, though critically, they have been received somewhat poorly. Iron Lung is distinct among these as a truly indie project (an indie film based on an indie game). As such, the approach the film has towards its source material is very different from its contemporaries. In Iron Lung, the game is used almost like a canvas upon which the film paints a more detailed picture of the world and characters that were present in the game. The set and many of the props are taken directly from the game. However, the story expands greatly upon the barebones setup of the original game, answering many questions that players would have had, but creating even more questions and keeping some things mysterious.
The film is an excellent debut film from a talented filmmaker. While the context of the film’s production may color the perception of viewers who are aware of it, the film stands on its own as an engaging and tense horror-thriller. The film has an undeniably slow pace, and the middle portion especially can begin to grow slightly boring. However, most of the time there is just enough going on, just enough mystery, and just enough interesting character work or worldbuilding to keep the audience invested in what is going to happen next. While the film answers many of the conundrums posed by the original game, it doesn’t sacrifice the uncertainty and ambiguity that contributed so immensely to the horror of the game.
Iron Lung consistently manages to make the incredibly limited space of the film visually interesting by placing the camera in nearly every location possible. The set design is incredibly faithful to the source material and yet brings in enough new and interesting elements to the space that even those familiar with the original game aren’t bored. The visual effects are, with the exception of one or two particularly ambitious moments, convincing enough to maintain immersion in the world. This feat is especially impressive with the film’s miniscule budget compared to other films in the sci-fi horror genre.
While Fischbach’s acting is enough to support the film’s script, he is regularly upstaged by the actors and actresses around him. Caroline Rose Caplan’s performance particularly stands out, especially due to her ability to communicate intense emotions without the audience seeing her face for most of the film. Mick Lauer and Elsie Lovelock are also standouts despite their short screentime. Overall, the film is an imperfect masterpiece that demands attention as an anomaly in the world of film: a successful movie made entirely independent of the Hollywood system.
Iron Lung could establish a new precedent for influencers and content creators to become influential creatives offline in areas such as film and television. On February 24, A24 released the trailer for The Backrooms, directed by Kane Parsons, better known as Kane Pixels on YouTube. The upcoming film is based on Parsons’ YouTube series, which itself is an adaptation of a 4chan post and the mythology created around it. Generally, animation creators originating from YouTube have been experiencing great success. Shows such as Murder Drones, The Amazing Digital Circus, and Hazbin Hotel, which all started out on YouTube, as well as Smiling Friends which was created by YouTubers Zach Hadel and Michael Cusack, have all found homes on streaming platforms right alongside more traditional film and television.
