Rating: ★★★​​★

Directed by Markiplier

Starring Markiplier, Caroline Kaplan, Troy Baker, Jacksepticeye

Rated R

Release Date: Jan. 30, 2026

After posting his playthrough of David Szymanski’s “Iron Lung” to YouTube in 2022, Markiplier approached the creator with an idea to translate this indie horror game to the big screen — fully financed and directed by the beloved YouTuber himself. What followed was a three-year labor of devotion to acting, directing, and producing — one that now arrives as a serious entry in the growing canon of horror video game adaptations.

We open on the Convict (Markiplier): Guilty of unspeakable crimes against humanity, he is condemned to carry out his sentence submerged in a blood ocean. His submarine, nicknamed the “Iron Lung,” becomes a crucible of mental and emotional reckoning. With no other recourse, he navigates the ocean floor, snapping X-ray photographs of what lurks behind welded metal walls. As his defenses and oxygen supply slowly dwindle, his only path to the surface — and redemption — is to plunge deeper into the recesses of the ocean and his own mind, no matter the cost.

The claustrophobic layout of the submarine — the film’s singular setting — paired with Markiplier’s one-man performance presents an obvious yet intriguing narrative challenge, one which the YouTuber takes in stride. His directorial instincts pleasantly surprise: Keeping the set design entirely faithful to the game, Markiplier employs nauseous camera angles, tense action shots, and eerie lighting choices that make full use of the cramped space. After a while, all that the Convict — and the viewer — knows of the world are green indicator lights, flashing proximity alerts, and the slow but inevitable condensation of blood through metal.

On top of the visuals, the sound design is nothing short of phenomenal. Rather than relying on ambience alone, Andrew Hulshult’s tectonic score imbues every indiscriminate creak and groan with the presence of alien life. Guttural, metallic synths swell and reverberate through your skull, pulling you inside that subhuman metal box where madness and despair seep in. Every sound penetrates the sanguine abyss, asking: What is real, and what is merely an invention of the mind?

However, “Iron Lung” is not without its fractures. The story and heart of the film are as much Markiplier’s creative property as the original game itself, and viewers who are unfamiliar with either may find stretches of button-pushing and lever-steering, key components of the gameplay, to be slow and aimless — and rightfully so. The Convict’s backstory and fraught ties to the upper world are barely explored. His captors are unflinching and backstabbing with little explanation for their motives. The film doesn’t pick up the pace until its latter half; before then, viewers must trust in the suspenseful atmosphere Markiplier meticulously builds.

And then, there is Markiplier himself, a double-edged sword to his own project. A film this stripped-down hinges almost entirely on how compelling — and entertaining — its lone subject can be. 

For fans, it is simply impossible to separate the Convict from Markiplier. Every familiar mannerism, sigh, and curse of exasperation yanked me, and my fellow theatergoers, out of the film in fond amusement of the YouTuber, not the Convict. Speaking for the millions of fans who showered the box office on opening weekend, I felt immense pride watching one of my favorite YouTubers grace the theater in one giant leap for a new generation of creatives.

For unfamiliar viewers, there is still much to admire in someone without “professional” acting experience. Forgiving his initial awkwardness in the role, Markiplier’s cautious performance gains strength and depth as the film progresses and reality cracks. By the final act, he has shed the role of a creator and grown into the Convict — hollow, lost, and forced to confront the cosmic horror of his situation. 

“Iron Lung” is far from perfect, but it’s got a spark and a fandom willing to follow its maker into uncharted creative depths. In his first major theatrical release, Markiplier stakes his claim as more than an online content creator, with ambitions that extend far beyond our computer screens. In a year chock-full of upcoming horror video game adaptations, “Iron Lung” sets a high bar, ushering in an era of self-serious, imaginative indie horror where vision and dedication can outshine big budgets and studio backing.