Movie · 2026 · Horror, Mystery, Science Fiction · 2h 5m · R · English
Curator score: 2.5/10 (333.9K ratings)
This is not an expedition. It's an execution.
Overview
In a post-apocalyptic future where an event known as "The Quiet Rapture" caused all known stars and habitable planets in the universe to disappear, a convict is sent to search an ocean of blood discovered on a desolate moon, using a small submarine nicknamed the "Iron Lung".
Ratings
Curator score: 2.5/10
IMDb: 5.9/10
Letterboxd: 3.14/5
Metacritic: 54
TMDB: 7.0/10
Director
Mark Fischbach
Production
Markiplier Studios
Cast
Mark Fischbach, Caroline Kaplan, Troy Baker, Elsie Lovelock, Elle LaMont, Mick Lauer, Dave Pettitt, Holt Boggs, Isaac McKee, Roman Parsons Crow, River Van Coleman Crow, Townes Blaine Crow, Asher Wagh, Kazuki Jalal, Alanah Pearce, Seán McLoughlin, David Szymanski, Danielle Evon Ploeger, Rahul Kohli, Ethan Nestor
Curator Review
Verdict
A lean, nasty sci-fi horror premise with a strong survival hook and a memorable visual conceit, but the feature-length expansion seems to strain the source material and the storytelling can get incoherent. Best approached as a grim, effects-driven genre ride rather than a tightly plotted mystery.
Best for
fans of claustrophobic survival horror
viewers who like extreme body-horror and gore
audiences curious about game-to-film adaptations
people who enjoy bleak, high-concept sci-fi settings
Skip if
you need airtight plotting and clear worldbuilding
you dislike gore or body-horror
you want a polished mainstream studio sci-fi film
you are not interested in internet-culture-adjacent filmmaking
Overview
Iron Lung has a premise that does the heavy lifting: a condemned diver in a tiny submarine, an ocean of blood, and a universe stripped of stars. That’s the kind of setup that can carry a movie on atmosphere alone, and this one clearly understands the value of confinement, dread, and escalating bodily horror.
Worth noting
What makes it work best is the commitment to the bit. The film feels handmade and aggressively genre-forward, with a late stretch that reportedly goes full splatter-metal. There’s a real sense of a creator stretching a game concept into a proper feature, and when the tension is focused, the result is nasty, tense, and memorable.
Bottom line
The downside is that the expansion can show. The story appears to drift into muddled territory as it tries to pad a short-form concept into a longer runtime, and some viewers will feel the logic slipping under the pressure of spectacle. If you’re here for mood, gore, and a singular nightmare image, it delivers. If you’re here for elegant sci-fi storytelling, it may leave you cold.
Top Letterboxd reviews
-ˏˋ mak ˊˎ- (2.5★) · 21192 likes
now i need the director’s cut with markiplier in the top left corner reacting like he’s playing a video game
Emily (3.5★) · 12505 likes
this happens to women once a month
frejaoneill (3★) · 7444 likes
(i don’t usually write long reviews but i don’t want people to start attacking me for my rating so here is an explanation)
gonna give credit where credit is due, this film is VERY well made! usually for these kinds of films it feels like i’m just watching a youtube short at the cinema but this time it actually felt like a full length film which is very refreshing to see
everything about this film in terms of filmmaking is… more
Brad Stowell (3★) · 6027 likes
mad respect to Markiplier for using his gamertag as the writing and directing credit
cob (3★) · 5984 likes
last 15 minutes is some of the most metal shit you’ll see all year, evil dead (2013) levels of blood