Iron Lung is a 2026 American science fiction horror film written and directed by Mark Fischbach, credited under his online alias Markiplier, in his feature directorial debut. It is based on the 2022 video game by David Szymanski. The film stars Fischbach, Caroline Rose Kaplan, Troy Baker, Elsie Lovelock, Elle LaMont, Seán McLoughlin, and Isaac McKee. The plot follows a convict named Simon (Fischbach) who is forced to pilot a submarine through a desolate moon's ocean of blood, after an event known as the Quiet Rapture caused the majority of humanity and all stars to disappear without warning. Development on a Iron Lung film adaptation began in April 2023, when Fischbach announced he would be adapting the game. Iron Lung was released in North America on January 30, 2026, to mixed reviews from critics. It was a financial success, grossing $23 million against a production budget of $3 million.