The Fantastic Four: First Steps' runtime has been revealed – and so have some huge spoilers about the Marvel Phase 6 movie's plot

• The official runtime for The Fantastic Four: First Steps has reportedly been confirmed
• Marvel's next big-screen offering will be the longest movie since Guardians of the Galaxy 3
• The reveal comes as major story spoilers seemingly leak online

The Fantastic Four: First Steps' official runtime has apparently been revealed, but that's not the only information about the forthcoming Marvel movie that's circulating online.

According to US movie chain AMC Theaters, the group's Marvel Cinematic Universe (MCU) debut clocks in at two hours and 10 minutes. That would make it the longest superhero film Marvel has made since 2023's Guardians of the Galaxy Volume 3, which ran for two hours and 29 minutes.

As I said, though, this isn't the only detail that's recently emerged online about the Marvel Phase 6 flick. It also appears that potentially huge spoilers about First Steps' story have hit the internet.

According to those in the know, including industry insiders ViewerAnon (see above) and Jeff Sneider, a preview screening of one of 2025's most anticipated new movies was held in Los Angeles on May 28. The chances are that those in attendance would have had to sign a non-disclosure agreement that bars them from discussing the film, but it appears that one individual has ignored that and revealed some major plot details anyway.

You won't find links and/or sources to the alleged leak here, nor will I describe what I've read about The Fantastic Four's next silver-screen adventure. This is more of a public service announcement to forewarn you that, as of yesterday (May 29), massive story spoilers are doing the rounds online.

So, if you want to watch the latest film to star Marvel's First Family without prior knowledge of what happens in it, I'd advise you to mute certain words and hashtags on social media regarding First Steps. It might be worth staying away from certain Reddit pages and other online forums for the time being until discussions about said leak die down, too.

Everything we officially know so far about The Fantastic Four: First Steps

Thankfully, there's a wealth of concrete and spoiler-free information about The Fantastic Four: First Steps that you can read about instead.

Let's start with that all-important release date, and the actors who'll play the titular team. The Fantastic Four: First Steps will arrive in theaters worldwide on July 25, 2025. The iconic quartet will be played by Pedro Pascal (Reed Richards/Mister Fantastic), Vanessa Kirby (Sue Storm/The Invisible Woman), Joseph Quinn (Johnny Stormy/The Human Torch), and Ebon Moss-Bachrach (Ben Grimm/The Thing), too.

Joining them on the cast roster are Ralph Ineson as Galactus and Julia Garner as The Silver Surfer, with the British duo playing the film's primary and secondary antagonists. Rounding out the cast are John Malkovich and Paul Walter Houser in roles that haven't been revealed publicly yet, and Natasha Lyonne, who's similarly been cast in an undisclosed role.

On the official story revelation front, back in February The Fantastic Four: First Steps' poster confirmed that this movie won't be set in the MCU. A few months later, Marvel president Kevin Feige revealed that it would be a period piece that's set in an alternate dimension to Earth-616, aka the main universe at the center of the MCU.

As mentioned, Galactus is set to be the movie's villain-in-chief. First Steps' main villain was all but confirmed via a Marvel.com article in April 2024, but it wasn't until a year later that a leaked Lego set revealed our first look at Galactus.

While the initial trailer for First Steps unveiled the first official look at The Fantastic Four and other characters who'll populate the film, it only briefly teased what the celestial being known as the 'Devourer of Worlds' would look like.

More recently, First Steps' official trailer finally introduced us to Garner's Silver Surfer and showed off Mister Fantastic's stretchy powers. Prior to the latter's public release, a CinemaCon teaser confirmed a big fan theory about Sue Storm, too.

Lastly, the post-credits scene of Thunderbolts*, the latest MCU film to hit theaters, dropped a big hint about how The Fantastic Four will wind up in the MCU. Check out my Thunderbolts* ending explained article for spoiler-filled details on what was shown.

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