It was only a matter of time before YouTubers started making movies. Last year, NEON released former YouTube critic Chris Stuckmann’s horror film Shelby Oaks, and now the individual known as Markiplier (real name: Mark Fischbach) is self-releasing his own directorial debut, Iron Lung. Obviously, there’s a world of difference between making an online video and a feature-length motion picture. This guy has a vision, though, and while he has room to grow as a director, it’s an admirable effort.
The story begins with a short explanation of “The Quiet Rapture,” an apocalyptic event that eradicated all the stars and habitable planets in the universe. Only a small number of people survive. One of them is a convict named Simon (Fischbach). As punishment for his crimes, he’s welded into a rickety iron submarine and plunged into an ocean of blood that’s been found on a moon somewhere. He’s supposed to use a special x-ray camera to take pictures of what’s down there. No one – not even mission captain Ava (Caroline Rose Kaplan), who speaks to him over the radio – could predict what he finds.
Markiplier has a good grasp on atmosphere. Iron Lung is two hours of a single actor inside a single, cramped location. That could become excessively boring to look at. He relies on Dutch angles, closeups of dashboard instruments, and shots of dripping pipes to break up the visual monotony and make the sub’s interior seem appropriately claustrophobic. Sound design contributes to the effect, creating a feeling of paranoia that it could implode. Other times, whatever is outside the sub makes eerie noise. (No spoilers here.) The film achieves its goal of placing viewers inside the metal deathtrap right alongside Simon, building a consistent sense of anxiety.
Challenges present themselves to our protagonist throughout. Sometimes he tries to fix faulty, outdated equipment; other times he attempts to navigate the sub to obtain a sample of what he discovers at the bottom of the blood ocean. These regularly arriving obstacles increase in intensity, adding layers of impending doom. The movie deserves extra credit for its finale, a literal bloodbath that is alleged to have broken the world record for the largest volume of fake blood ever used onscreen. It’s shocking to see – a suitably catastrophic sight for a plot that’s always edging closer and closer toward the horrific.
Markiplier needs a little work in sharpening his storytelling skills. In a few spots, it isn’t completely clear what’s going on. I had to read a detailed plot synopsis on Wikipedia afterward to understand one particular revelation. And, as is often the case with first-time directors, he falls a little too in love with his own material. If you can’t get on the film’s wavelength, the occasionally slow pacing may drive you mad. Editing the 127-minute running time by 20 or 25 minutes would have maximized the suspense.
Although those are not insignificant flaws, I have to admire what Markiplier has done. With only a $3 million budget, he’s crafted a nerve-rattling descent into hell. The joy and enthusiasm he has for adapting David Szymanski’s video game is palpable. Calling a movie a “passion project” is cliched, but in this case, that passion comes right off the screen, marking Iron Lung as a noteworthy debut from a creator with a bright future.
out of four
Iron Lung is rated R for language, bloody images, and some gore. The running time is 2 hours and 7 minutes.
© 2026 Mike McGranaghan