‘Iron Lung’ Review: Markiplier’s Feature Directorial Debut Is Actually Really Good

Does Markiplier’s directorial debut live up to the hype? Ahead, find our honest review of the film.

What happens when you send the guy from Five Nights at Freddy’s playthroughs into space and subject him to two hours of cosmic horrors beyond comprehension? Apparently, you get Iron Lung, the directorial debut from Mark Fischbach, best known as Markiplier. 

The film is an ambitious undertaking, based on the 2022 Iron Lung video game by David Szymanski. Fischbach first did a playthrough of the game on his YouTube channel upon its release, and it was just shy of a year later that he would announce that the game would be adapted to film with him at the helm. Now, almost three years on (and plenty of production hiccups along the way), Fischbach’s directorial debut has finally hit Malaysian cinemas thanks to lobbying from dedicated fans.

The idea of a YouTuber movie is already a daunting concept for critics, but it’s safe to say we’ve come a long way from Smosh: The Movie! And Ryan and Sean’s Not So Excellent Adventure. Iron Lung puts Fischbach’s directorial prowess on full display and proves that a big budget and extensive manpower aren’t necessary to create good art. It’s a little unpolished in areas, but overall, it’s a really solid production that rivals a lot of major blockbusters with far bigger budgets. 

The real question for prospective audiences is whether the film stands on its own as a feat of independent cinema, if it’s a love letter to the game’s built-in fanbase, or if it’s a film that’s just for Markiplier fans. As a whole, it’s very much the former—and, for those worried, you don’t have to be massively familiar with the Markiplier YouTubeverse nor have any context on the game before watching this film to enjoy it. 

[Minor spoilers ahead]

Deep, deep down

The film takes place in an alternate universe where humanity has colonised space, and an event called the “Quiet Rapture” causes all stars and habitable planets to disappear. All that remains are humans on space stations and spaceships, split into two conflicting organisations: the Consolidation of Iron (C.O.I), made up of three space stations and two spacecrafts; and Eden, the largest space station. Surrounding the stations are four desolate moons that have become flooded with an ocean of blood, believed to contain vital resources that can sustain human life. 

Our protagonist, Simon (played by Fischbach), is a convict from Eden imprisoned for his role in the destruction of the C.O.I.’s Filament Station. In exchange for his freedom, he is brought on an expedition to explore one of the blood moons, where he is tasked with piloting the ramshackle submarine SM-13, also known as the “Iron Lung”.

Simon is given absolutely no information about this expedition. Instead, he’s told he’s the first convict to be sent down (not true) and that his job is just to collect data and samples. It doesn’t sound like too bad a gig, but when you consider that he’s welded into the submarine from outside with no way for him to escape, and the fact that the crew will not stop ragging on him from the safety of the mothership, it’s a pretty bleak setup. And, to make things worse, he’s lied to for basically the entire film, which culminates in the most valid crashout of all time—three times over. 

Without spoiling too much, the movie basically follows both his descent into madness and his redemption, and you, as a viewer, are forced to experience it through his eyes. Between radiation sickness, alcohol poisoning, a concussion, and an Eldritch beast, Simon is not having a good time, to say the least. By the climax of the movie, you’re just praying it all comes to an end for his sake. That’s not to say that the story doesn’t have a satisfying conclusion, however. By forcing you into Simon’s perspective, the progression of the plot has you rooting for him more and more, which makes the emotional impact of the third act that much more poignant.

Oh, the horrors!

One strength of the film is how it seamlessly translates the first-person, immersive experience of video game horror to the big screen through clever gimmicks and visuals. For a start, the X-ray camera is an incredibly unique and terrifying device, hitting all the pain points effectively. It serves as both a jump scare and a suspense builder, disorienting you to the surroundings and obfuscating the Big Bad monster until it’s already too late.

Further, because we’re seeing everything through Simon, you cannot separate yourself from the situation. In many ways, we are Simon, and as such, much like in a game, you feel a sense of agency as the audience. Simon’s not a dumb horror trope, either—he’s a flawed and complex character that behaves like a real person. Everything he does in the film is deeply rooted in logic, at least as far as it can be given his ever-declining state of mind. Because of this, and because you end up becoming Simon for the duration of the film, it keeps you on the lookout for ways to break out of the system, and whether or not it’s possible, you can’t help but try. All of this just adds a further layer of horror to the watching experience.

Drawing the lines

For better or worse, Fischbach is carrying the movie. There are only a few minor appearances from the crew throughout the film’s two-hour runtime, so you either have to buy him as Simon or be taken out of the story entirely. Fortunately, Fischbach’s performance is really solid—there are, of course, highs and lows, but for the most part, he embodies the character really well.

Also lending greatly to his performance is the film’s script. We learn a lot more about Simon and the world of Iron Lung not through exposition, but through clever dialogue and interesting visuals, which is a breath of fresh air in the era of spoon-fed plots. Fischbach also sneaks in funny quips and jokes that humanise Simon and help to cut the tension, and he does it in a way that doesn’t detract from the urgency of the story whatsoever. For me, the only time things get a bit iffy is during the latter monologues in the film, but that had more to do with the performances of the supporting cast than the actual script itself.

Further, the cinematography was incredibly creative, driving home the claustrophobic atmosphere of the submarine set and putting you in Simon’s shoes. There were also so many clever camera tricks and transitions that made the movie really interesting visually, despite the low budget and small set. Speaking of the set, opting for a practical set was the right move for the production, adding a very visceral feel to the film. 

Practical effects, in general, are where the film shines. Fischbach’s hair, makeup, and wardrobe sell you on the convict character, and the prosthetics that come in later on are very well done. One thing that doesn’t always land for me, however, is the fake blood. Fun fact: Iron Lung supposedly holds the record for most fake blood in a movie, containing approximately 300,000 litres and beating the 190,000 litres used in Evil Dead (2013). It may be a combination of the lighting in certain scenes or the texture of the fake blood itself, but it does occasionally lean a bit costumey at times. That said, it’s more than made up for by all the other moving parts in this film.

Timing is everything

The film is paced really well, leaving enough time to get you acquainted with the world and immerse yourself in the lore, which is especially great if you’re someone who hasn’t played the game before. Further, the stakes are already so high from the get-go, so having regular little breathers to sit with what’s happening and really empathise with Simon’s plight helps drive home the third act’s action-packed sequence that much more.

The sound design does a lot to help alleviate the slowness in the film, too—even when things aren’t necessarily kicking off on screen, the score and sound effects help massively to keep you engaged.

Final Verdict

At the end of the day, Iron Lung is a passion project that was well worth the trouble. Fischbach may not be the first YouTuber to branch into feature films—famously, RackaRacka’s Danny and Michael Philippou penned and directed the award-winning cult horrors Talk to Me (2022) and Bring Her Back (2025)—but he is the first to break box office records with a self-written, self-financed, self-edited, and self-starring production. With a shoestring budget of just over US$4 million, it has managed to bring in a box office revenue of over US$50 million—an objective win for independent cinema.

Is it a perfect movie? No, not by any means. But as far as sci-fi horror goes, it’s a really intriguing and entertaining watch, and it shows a lot of potential for Mark Fischbach’s future directorial career. Will I be jumping at the bit to go on a submarine expedition, though? Hmm… probably not.

Score: 7/10

Iron Lung is in cinemas now at GSC, TGV, and OneCinema. 

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