Iron Lung
Adapted from Markiplier's horror game about exploring a blood ocean in a submarine
The brief
Markiplier's feature debut adapts his own claustrophobic horror game into something that feels like Alien crossed with Das Boot, trapping you inside a rusty submarine descending through literal oceans of blood. The YouTuber-turned-filmmaker commits fully to the cosmic dread, building tension through mechanical groans and the protagonist's increasingly unhinged isolation rather than cheap jumpscares. At over two hours, it's deliberately paced like a slow burn thriller, letting paranoia seep in as you realize escape was never the point. Perfect for fans of cosmic horror like Event Horizon or anyone who thinks most modern horror moves too fast and shows too much.
The verdict
If you crave atmospheric cosmic horror that prioritizes slow-building dread over instant gratification, this claustrophobic submarine nightmare delivers genuine terror through isolation and mechanical decay. If you need faster pacing or frequent scares to stay engaged, the deliberate two-hour descent will test your patience more than your nerves.
Watch with
- 👤 Horror fans who appreciate slow builds
- 👥 Friends who enjoy discussing cosmic dread
- ⚠️ Those sensitive to claustrophobia should skip
Heads up
- Intense claustrophobic scenarios throughout (frequent)
- Graphic bloody imagery and gore (moderate)
- Psychological deterioration and isolation (frequent)
- Disturbing cosmic horror themes (moderate)
Credits
- Director
- Markiplier
- Cast
- Markiplier, Caroline Kaplan, Troy Baker, Elsie Lovelock, Elle LaMont, Valkyrae, Seán McLoughlin
Official synopsis
An ocean of blood. The only hope left after The Quiet Rapture. In the rusting halls of crumbling space stations,
The Double
Make a night of it
Pair this with The Thing Expanded (2026)
Both trap isolated protagonists in claustrophobic spaces facing unseen horrors.
