Everything We Know About Markiplier’s ‘Iron Lung’: Setting, Cast, and More

Announced around two years ago, YouTuber Markiplier’s efforts to bring the influential indie horror video game Iron Lung to the big screen have been largely shrouded in mystery. The film, which will serve as Mark ‘Markiplier‘ Fischbach’s directorial debut, is reportedly already finished filming – and though fans of the game (and of Fischbach) are waiting with bated breath for news on a release date, the truth is that all that we know is that the movie is “coming soon“.

The game, a one-man project created by David Szymanski, follows a convict sentenced to enter a sealed submersible and dive deep into an ocean made of what appears to be blood. As the convict, you pilot the submarine to various points of interest in order to take photos of what lurks within the blood ocean, all for the scientific advancement of what remains of humanity following an apocalyptic event left the vast majority of humans, and planets, missing from the known Universe.

If that sounds like a massive premise, know that the game is only about one-to-two hours long (depending on how you play it), and doesn’t explain much in the way of details. Rather, it hints at larger events while keeping you, as the player, largely in the dark – welded inside a submarine at the bottom of an ocean as you are. We’ll go a bit more into the world of Iron Lung below, but if you’re interested in checking out the game for yourself, you can find it on Steam.

Watch the ‘Iron Lung’ Teaser Trailer

While Fischbach has largely kept his cards close to his chest in regards to Iron Lung, he did drop a teaser trailer for the film in 2023, and a second teaser in 2024.

It doesn’t show a lot, but it does show a lot of blood. In fact, Fischbach was hospitalised during filming due to extreme exposure to fake blood in an attempt to set the record for “most blood in a horror movie”. That’s dedication to your craft, people.

‘Iron Lung’ Cast – Confirmed List

While the game really only features one character, the player, the Iron Lung movie adaptation is going to blow that open with four whole actors involved. Or maybe five, we’ll see. Here’s everyone we know is in the Iron Lung movie:

• Mark ‘Markiplier’ Fischbach as the Convict
• Seán ‘Jacksepticeye’ McLoughlin as ‘Voice on Speaker 2’
• Caroline Kaplan
• Elle LaMont

It’s a short list, but there are also rumours that the game’s creator, David Szymanski, will appear in a cameo.

When is ‘Iron Lung’ Coming Out?

The simple answer is: soon*.

The more complex answer is that, according to Markiplier, the project is nearly there. While Fischbah has been working on the Iron Lung movie for the past two years, alongside his own YouTube channel and podcasting efforts, he’s also been working on a horror anthology series, The Edge of Sleep, which launches May 15, 2025 on Tubi.

Plus, while Fischbah confirmed that the movie was “officially done” and that filming has wrapped, his efforts since have gone into trying to get the movie out in theatres: something he says will happen, but that dealing with theatres is a “complicated process”.

“This has been the longest run of pure work that I’ve ever done in my entire life,” Fischbah said in 2024. ” been the most arduous thing that I’ve ever taken on. It has required the most of my concentration for the longest period of time than anything I’ve ever done.”

What is ‘Iron Lung’?

As mentioned above, Iron Lung is a 2022 horror video game released by David Szymanski that sees you pilot a submersible through an ocean of blood.

If you’re comfortable having some details about the world of Iron Lung spoiled for you before you see the movie, read on. Otherwise, we’ll update this story when we have more concrete answers about the movie’s release timing.

Spoilers Below.

Iron Lung takes place in a universe where, in an event that came to be known as ‘The Quiet Rapture’, every known star and habitable planet disappeared in an instant – along with any human that was on them. This left only those who were aboard space stations or starships alive, and those who did survive were left with almost no supplies or contact with one another. At the same time, a number of moons with oceans of blood (yes, human blood) appeared in space.

Following ‘The Quiet Rapture’, humanity split into two factions as far as we know, namely, the ‘Consolidation of Iron’ (C.O.I) and ‘Eden’.

The C.O.I is an organisation made up of three space stations and two space crafts, and is largely run by a voting system, where all of its 257 ‘citizens’ decide things collectively. It had a fourth space station, Filament Station, which was left uninhabitable due to the actions of Eden following a nine-day battle over the station.

Eden is what remains of a space station that used to orbit Mars – the largest man-made structure that still exists, and which, as far as anyone knows, houses the only remaining trees in the universe. It has a population of 468, meaning there are fewer than 1,000 humans left in the universe of Iron Lung. Bleak.

Prisoners taken by the C.O.I. during the nine-day battle with Eden have been undergoing a process known as ‘conviction realisation’, which is a fancy way of saying they’re being sent on missions into the newly-appeared blood moons to search for resources – anything that could give humanity a chance at survival. However, there are rumours that these convicts are not meant to return, and are instead sent to die in the oceans.

This is where the game begins: you are a convict and are being sent into the blood ocean on the moon ‘AT-5’. Your goal is to search the ocean for anything of interest, using a camera attached to the outside of the submarine to take photos of what is found within the blood. There have been several convicts that have gone before you, and now it’s your turn.

What is found within the blood oceans? Well, there’s a bunch of ruins – things that look strangely man-made – as well as unidentified objects, the remains of never-before-seen creatures, as well as some that are still alive. Good luck!