Markiplier's Iron Lung scores impressive $17.8 million US opening weekend, but it was beaten to the top spot by Evil Dead director's new horror movie Send Help

Markiplier's directorial debut, Iron Lung, scored a very impressive opening weekend at the box office.

The sci-fi horror stars YouTuber Markiplier, real name Mark Fischbach, who also writes, directs, and stars. The story revolves around a convict (Markiplier's character) who, on a post-apocalyptic moon, must use a submarine – that he's welded inside of – to go on a mission through an ocean made of blood. It's based on the 2022 video game of the same name.

In the US, the film debuted to a massive $17.8 million haul, up against a reported budget of under $3 million, according to Deadline. Box Office Mojo puts the worldwide figure at $21.7 million.

That means Iron Lung came in at number two on the US box office charts this weekend, beaten only by Sam Raimi's new film Send Help at $20 million (though Deadline's report indicates the actual figure might be $18 million). That survival horror movie stars Rachel McAdams and Dylan O'Brien, and it sees a woman stranded on a desert island with her tyrannical boss. Box Office Mojo puts the worldwide total at $28.1 million, with a $20 million domestic haul.

Iron Lung stands at a middling 50% critics' score on Rotten Tomatoes, but a much stronger audience score of 89%. Along with Markiplier, it also stars Caroline Rose Kaplan, Troy Baker, Elsie Lovelock, Elle LaMont, David Pettitt, and Seán McLoughlin.

You can catch the movie in theaters now. For even more, you can check out our guide to all the upcoming horror movies, or the best horror movies to watch now.