While Marvel Studios has already cast one member for their future MCU Fantastic Four film, they still need to cast three other actors to star alongside John Krasinski and make the perfect First Family. Featured in Doctor Strange in the Multiverse of Madness, Krasinki played Reed Richards, aka Mr. Fantastic. While this was the fulfillment of many online hopes for the Jack Ryan, A Quiet Place, and The Office star, there are subsequent fan casts for the rest of the Fantastic Four who would compliment Krasinski's Mr. Fantastic extremely well should he return in the MCU.

In Doctor Strange in the Multiverse of Madness, the Stephen Strange (Benedict Cumberbatch) of the Earth-616 found himself in another universe alongside newcomer America Chavez (Xochitl Gomez) whose power to travel the Multiverse was desired by the corrupted Scarlet Witch (Elizabeth Olsen). Strange and Chavez found themselves in the custody of the Illuminati, a team of this alternate universe's greatest heroes and leaders. Not only did this team include Charles Xavier of the X-Men with Sir Patrick Stewart reprising his iconic role, but it also saw actor Anson Mount's return as the Inhuman king Black Bolt from the 2017 Inhumans television series. However, the biggest reveal of this superhero team was undeniably Reed Richards which paid off a long-hyped fan casting theory.

Related: John Krasinski's Fantastic Four Movie Is Getting Really Likely

Hopefully, Marvel Studios decides to keep Krasinki in the role of Reed Richards in the primary MCU. It would certainly allow Marvel Studios to reboot the Fantastic Four franchise by putting their best foot forward - with Krasinski an immensely popular choice for the role. Likewise, some corresponding picks that align with contemporary choices for the Fantastic Four would make his role as Mr. Fantastic even more dynamic and entertaining. Here are the top choices for actors who should join John Krasinski's Mr. Fantastic in the MCU's Fantastic Four.

Why John Krasinski Should Return As The MCU's Mister Fantastic

John Krasinski as Reed Richards in Marvel fan art.

Historically, the Fantastic Four franchise hasn't been all that successful, particularly the most recent attempt to reboot the franchise in 2015 from director Josh Trank. Now that Marvel Studios has reacquired the rights to the X-Men and Fantastic Four franchises following Disney's purchase of 20th Century Fox, the MCU can breathe new life into the superhero family. As such, it stands to reason that casting the internet's top choice for Reed Richards is an ingenious way to build hype and fan support. However, debuting Krasinski's Mr. Fantastic in Doctor Strange 2 as a variant was a brilliant way to test the waters effectively. The audience reception to Krasinski's cameo has been positive, and it would make sense for the MCU to build on the goodwill they've created by having Krasinski return as the primary Reed Richards for the upcoming Fantastic Four film in development (likely releasing in 2024 or 2025).

Emily Blunt As Sue Storm/The Invisible Woman

Emily Blunt Invisible Woman Fantastic Four

Due to their dynamic chemistry in A Quiet Place and its sequel, which Krasinki wrote and directed, Emily Blunt has been linked to the role of Sue Storm, aka the Invisible Woman, for just as long as Krasinki was linked to the role of Reed. Blunt was also first choice to play Black Widow before the role ultimately went to Scarlett Johansson, so to see her finally entering the MCU would be exciting. Another great wrinkle here is that Blunt and Krasinski are married in real life, a meta-dynamic that would undoubtedly be a major draw for audiences, just as it was for Krasinski's blockbuster horror films. After all, there's no better way to kickstart Marvel's First Family than with a real family bringing them to life.

The Rock as Ben Grimm/The Thing

Casting-Dwayne-The-Rock-Johnson-As-The-Thing

Next on the list of vaunted Fantastic Four casting theories is Dwayne "The Rock" Johnson playing Ben Grimm, aka the Thing (Reed's best friend). Beyond the immensely satisfying concept of The Rock playing a super-strong superhero literally made of rocks, there are additional benefits to Johnson playing Ben Grimm in the MCU. Firstly, Johnson excels in action roles that also feature the opportunity for comedy. Considering Ben Grimm's snarky personality in the comics, it's certainly a role The Rock could easily tackle. It's not hard to hear the Thing's classic "It's clobberin' time!" with the same inflection and energy The Rock gives to "Can you smell what The Rock is cooking?" made famous from his days in WWE. He also has proven chemistry with Emily Blunt, as seen in Disney's Jungle Cruise.

Related: Doctor Strange 2's Post-Credits Scenes Explained (They're Both Important)

While Dwayne Johson is committed to playing Black Adam in the DCEU, taking on the role of Thing would likely be less of a commitment if the MCU chooses to create Grimm predominantly with CGI. In this way, the Rock could simply offer his voice to MCU, similar to Vin Diesel, who voices Groot in the Guardians of the Galaxy films. It certainly seems like the best way for Johnson to be a part of both superhero universes simultaneously and would pay off another fan-favorite casting in the MCU.

Zac Efron As Johnny Storm/The Human Torch

casting Zac Efron in the MCU human torch

A longtime fan pick, Zac Efron should play the MCU's Human Torch. Not only could Efron bring the hot-headed recklessness and charisma Johnny is known for, but he'd also have no problem fulfilling the role of The Thing's primary annoyance (especially if Ben Grimm is played by The Rock). 2017's Baywatch perfectly displayed Efron and Johnson's hilarious chemistry where they comically antagonized each other while still working as an exciting action duo; a relationship that would hardly need any alterations if they were to play Johnny and Ben in the MCU. It should also be noted that the recently released film Firestarter sees Efron playing a father who helps his daughter control her fire powers. As such, it's become a fun meta draw for Efron's potential Johnny Storm casting.

As it stands, the MCU already has the internet's top choice for Reed Richards should Marvel Studios keep Krasinski. Therefore, casting the aforementioned actors for Sue, Ben, and Johnny (also top online picks) seems like a no-brainer. While it would undoubtedly be a relatively expensive cast, it wouldn't be a stretch to assume that Disney and Marvel Studios would be willing to pay the price, guaranteeing a successful box office from an IP that doesn't have the greatest track record. Whoever ends up playing Marvel's First Family in the upcoming Fantastic Four reboot, there are many hoping the team is finally given the justice it deserves in the MCU.

More: Doctor Strange 2 Confirms Best Fantastic Four MCU Origin Theory

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