Iron Lung: parents' guide
Best for ages 16 and up. Rated R for language, bloody images and some gore.
A grim, claustrophobic horror film for older teens and adults, written and directed by YouTuber Markiplier from a cult indie game. A convict pilots a tiny submarine through an ocean of blood on a distant moon, and the film is drenched in it: blood floods the cabin until he is swimming in it, and gory wounds, a severed arm and blistering skin pile up. Language is constant, with nearly 40 f-words. There's no sex. The horror is slow and oppressive, with monsters, hallucinations and a moment that suggests a death by suicide. Best for 16 and up.
What's in it
Violence
StrongVery bloody: blood pours and sprays into the sub until the pilot is swimming in it. Gory wounds, a severed hand and arm, a corpse-like figure missing part of its jaw, disfigured faces, spreading boils, and a man engulfed by a fireball in a flashback.
Language
StrongFrequent strong language, with nearly 40 f-words and about seven s-words, plus 'bullshit,' 'goddamn,' 'bastard,' 'ass,' 'damn' and 'hell.'
Sex and nudity
NoneNo sexual content or nudity; the lead is briefly shirtless.
Drinking, drugs and smoking
MildThe pilot drinks a small jar of medicinal rubbing alcohol with no visible effect. Otherwise no drinking, smoking or drug use.
Scary or intense scenes
StrongSustained, suffocating dread in a cramped, leaking sub: monsters glimpsed in grainy X-ray photos, disembodied voices, hallucinations, the pilot vomiting blood, and talk of drowning or suffocating on the ocean floor. One moment suggests a death by suicide.
Sensitive topics
- Suicide
Worth talking about
Simon is promised his freedom for a mission no one expects him to survive. What do people in power owe someone they treat as disposable?
Similar picks around 16+
Checked October 13th, 2026 against Common Sense Media, Plugged In, Wikipedia, movieguide.org, themoviespoiler.com, plotexplained.com, moviesense.io, cineparenting.com. The age is our judgment, not an official rating, and every family draws its lines differently: read the notes, not just the number. Spotted something we missed? Tell us. How we rate.