Iron Lung (video game)

Did You Know?

• Iron Lung was inspired by a visit Szymanski made to a Loch Ness museum in Scotland with his wife.
• The core concept centered on a cramped submarine where the player observes the environment through ultrasound-like images rather than a direct viewport.

Gameplay

The player pilots a midget submarine from a first-person perspective, confined to its single room. Navigation relies on a minimalist interface showing heading and position, with no viewing ports or ability to exit. A low-quality camera provides the only external view, used to take photographs that reveal surroundings and details. Scripted oxygen and pressure decreases occur but do not affect gameplay. Optional cheat codes include a rave mode and a Markiplier mode that replaces textures with the YouTuber's face.

Plot

After the Quiet Rapture causes all stars and habitable planets to vanish, a surviving colony sends a convict to explore a newly formed ocean of human blood on a desolate moon. The submarine, the SM-13 Iron Lung, has its hatch welded shut and viewport sealed, leaving only a front camera for observation. A note from a previous occupant warns the mission is a death sentence. The player navigates treacherous caves, photographing points of interest that reveal plant growth, unexplained rock formations, large skeletons, and artificial structures. A large face appears in one photograph but vanishes in the next. An orb of light causes violent shaking, and a massive sea monster attacks the submarine after its eye is photographed, causing a leak. A frogfish-like creature then smashes through the submarine, killing the player. A post-game text states no method exists to retrieve the Iron Lung or its photographs, but remains optimistic that humanity will find a solution.

Reception

Iron Lung received generally positive reviews. Aaron Boehm of Bloody Disgusting praised its oppressive atmosphere and exceptional sound design. Renata Price of Vice News linked its atmosphere to the systemic death spiral at the heart of capitalism. Zoey Handley of Destructoid argued its horror concept could only be fully realized in an interactive medium. In December 2023, a two-dollar price increase drew criticism and led to a sales drop. Following the Titan submersible implosion in June 2023, the game saw a surge in popularity, with comparisons drawn to the real-world event. Szymanski expressed discomfort, calling the situation horrific.

Film adaptation

On April 21, 2023, YouTuber Mark Fischbach (Markiplier) announced a self-financed film adaptation of Iron Lung, starring himself and Caroline Rose Kaplan, with his own script. David Szymanski assisted with the screenplay and made a cameo. The film, Fischbach's directorial debut, was co-produced by Will Hyde and Jeff Guerrero. A teaser trailer accompanied the announcement, an official trailer followed on October 14, 2023, and a final trailer on December 5, 2025. Released on January 30, 2026, in the US, Canada, UK, Australia, New Zealand, and parts of Europe, it grossed $50 million against a $4 million budget and received mixed reviews. Plans for DVD, Blu-ray, and digital release were announced on February 4, 2026. The film was released digitally on YouTube on May 29, 2026.