Iron Lung was a flop with Rotten Tomatoes critics — but its $21M box office debut is a huge win for independent horror

Iron Lung Shocks Hollywood with $21.5M Opening Weekend, Proving Indie Horror’s Box Office Power

In a stunning upset that has Hollywood buzzing, YouTuber-turned-filmmaker Markiplier’s Iron Lung has shattered expectations with a massive $21.5 million opening weekend at the box office. The self-financed horror film, based on David Szymanski’s indie video game of the same name, has outperformed many big-budget releases, including Sam Raimi’s star-studded Send Help. With a modest $3 million budget, Iron Lung’s success is being hailed as a triumph for independent filmmaking and a testament to the growing appetite for horror among audiences.

Markiplier, whose real name is Mark Fischbach, not only starred in the film but also directed it, making Iron Lung a deeply personal passion project. The film’s claustrophobic, anxiety-inducing atmosphere—faithfully adapted from the game—traps viewers in a tiny submarine as they explore an eerie ocean of blood. Critics and audiences alike have praised its ability to evoke dread, though the film has received mixed reviews, with a 44% critic score on Rotten Tomatoes compared to an 89% audience score.

Despite the polarized reception, Iron Lung’s box office performance speaks volumes. It has held its own against Raimi’s Send Help, proving that independent horror can compete with big-budget blockbusters. This success has reignited discussions about the potential of indie horror films, with many drawing parallels to the rise of Paranormal Activity in 2007, which went on to become a massive franchise after earning $194.2 million on a $215,000 budget.

The film’s success has also sparked hope for the future of independent cinema. Markiplier and Szymanski were visibly moved by the film’s reception, with both expressing gratitude to fans for their support. “I think it might be a big win for independent filmmaking,” Markiplier said in a recent interview, fighting back tears.

Iron Lung’s triumph is part of a broader resurgence in independent horror. Films like Good Boy, starring Indy the Dog, have also found success, earning $8.7 million on a $70,000 budget. These achievements highlight the genre’s potential to thrive outside the traditional Hollywood system.

As Iron Lung continues to draw audiences to theaters, its success serves as a powerful reminder that great storytelling and innovative filmmaking can come from anywhere. For Markiplier, this is just the beginning—and for independent horror, it’s a moment to celebrate.

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