Exclusive Excerpt

Marvel Secrets Revealed: Alternate Castings That Would Have Changed Everything

Chadwick Boseman as Drax. Alexander Skarsgård as Thor. John Krasinski as Captain America. An exclusive book excerpt dives into the formative days of the Marvel Cinematic Universe.
Chris Hemsworth in Thor 2011
Chris Hemsworth in Thor, 2011By AJ Pics / Alamy.

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The possibilities are always endless at the beginning of any universe. The same was true as Marvel Studios began assembling stars to lead its fleet of superhero films after the Big Bang of Robert Downey Jr.’s debut as Iron Man. In some cases, the outcome could have been radically different as the filmmakers and executives chose between actors. Imagine Chadwick Boseman not as Black Panther, but in Dave Bautista’s gray, tattooed alien role as Drax the Destroyer, or Jim from The Office getting ripped to portray Captain America. In an excerpt from the upcoming book MCU: The Reign of Marvel Studios, authors Joanna Robinson, Dave Gonzales, and Gavin Edwards reveal the paths not taken, starting with who could possibly bring the God of Thunder to life…

The Thor comic books drew from Viking mythology and the Norse Eddas, but they also regularly showcased the thunder god facing off against modern supervillains like the Absorbing Man. People liked to describe Thor’s language in the comic books as “Shakespearean,” by which they meant that, verily, Stan Lee hath sprinkleth Thor’s dialogue with enough archaic flourishes to make him feeleth like a man from another century.

The person hired to direct Thor, Kenneth Branagh, had directed many plays by the actual William Shakespeare, on stage and on screen, and saw connections that were deeper than Lee’s faux-Elizabethan language. “We’re interested in what goes on in the corridors of power, whether it’s the White House or whether it’s Buckingham Palace,” he said. “Shakespeare was interested in the lives of the medieval royal families, but he also raided the Roman myths and the Greek myths for the same purpose. I think Stan Lee went to the myths that Shakespeare hadn’t used.”

Branagh recognized that although the stakes in a Thor story were cosmic, the actors were human: “If the actors take those stakes seriously it is passionate and very intense. That observation of ordinary human—although they’re gods—frailties in people in positions of power is an obsession of great storytellers, including Shakespeare and including the Marvel universe.”

Feige had a slightly more contemporary cultural touchstone in mind: The Godfather. “It’s about fathers and sons, and it’s about the actions that a father takes that his sons will have to answer for,” he said.

While Marvel Studios had been aiming for one movie a year, in early 2009 it pushed the release date of Thor back to 2011. Even on that timetable, production was rushed. Ashley Edward Miller and Zack Stentz, who had been a writing team on the sci-fi TV shows Andromeda and Terminator: The Sarah Connor Chronicles, got a call from their agent. As Miller told the story, “Marvel was looking for television writers because they were fast. Hopefully, they were a team because that was even faster. And hopefully, they knew science fiction and comic books, and hopefully hopefully hopefully, they knew Thor.” Miller told Stentz, “I think we check off all the boxes.”

Soon the writers were in a meeting at the Marvel Studios HQ, discussing their take on the thunder god in front of a full room, including one guy they didn’t know, sporting a scraggly beard and wearing a T-shirt, jeans, and Chuck Taylor sneakers. But when he opened his mouth and spoke in a resonant, well-modulated British accent, the screenwriters realized it was Branagh. They got the job and started working with him, debating essential questions such as Thor’s role in the modern world and the name of Thor’s hammer. “One of my most vivid memories of those notes sessions,” Stentz said, “was Branagh didn’t like the name Mjölnir because it’s difficult to pronounce. He turned to all of us and asked, ‘Do we have to call the hammer ‘Mjölnir’? I see that it’s made out of some metal called ‘Uru.’ Could we call it Uru instead? Or would the fanboys string me up?’ Kevin [Feige] just gave his little half-smile: ‘Ken, the fanboys would string you up.’ ‘Alright. We won’t be doing that, then.’”

While Miller and Stentz labored over the script, Branagh worked with Marvel casting director Sarah Halley Finn. Stentz recalled seeing pretty much every notable Hollywood actress between the ages of twenty-five and thirty as they came by the production office to read for the role of Jane Foster, earthbound scientist and Thor’s love interest. He described Branagh’s reaction immediately following a meeting with Natalie Portman. “He was very taken with her,” Stentz said. “Not in a romantic way, but with her intelligence. Jane is a physicist, and we needed someone who could convey that intelligence. That’s what struck him about her: he said, forgive me, ‘Because the last thing we need is nuclear physicist Denise Richards.’” (Richards had played the nuclear physicist Dr. Christmas Jones in the James Bond movie The World Is Not Enough, earning much mockery and a 1999 Razzie Award for “Worst Supporting Actress.”)

Branagh was a draw for top-flight performers. Portman said she signed on because she figured that Branagh doing Thor was sure to be “super weird.” Anthony Hopkins joined the cast, playing the All-Father Odin, because he was a fan of Branagh’s theatrical work. But finding the right man for the title role proved more challenging. Finn said, “We were casting Cap and Thor in an overlapping period, and both of them seemed to be very risky.”

Jaimie Alexander  discusses a scene with director Kenneth Branagh on the set of THOR.
Jaimie Alexander (as Sif) discusses a scene with director Kenneth Branagh on the set of THOR.By Marvel Entertainment/PictureLux / The Hollywood Archive / Alamy.

Finn had tried out for the job of casting director on Iron Man; once she got the position, she never left. Although the Hollywood studio system had once valued behind-the-scenes continuity—to name just one example, costume designer Edith Head worked at Paramount Pictures for forty-four years, from 1924 to 1967, winning eight Academy Awards along the way—that approach had largely been discarded in favor of letting producers assemble a new staff for each movie. But Marvel Studios, valuing consistency and reliability, preferred to hire talented professionals and keep them around. Finn, like Louis D’Esposito and Victoria Alonso, would be a critical pillar in the new Marvel studio system. The ambition to create a shared universe of movies required an emphasis on continuity that molded not just the final films but the organizational structure behind the scenes.

Along with Jon Favreau, Finn had been an early advocate for Robert Downey Jr. On Iron Man 2, she had been behind the decision to hire Scarlett Johansson for the role of Black Widow, even though the actress wasn’t known for action movies or stunts. Finn said that Marvel had encouraged her to focus on the best actor for the character rather than securing the biggest name possible. Ironically, given her own status as a tenured employee of Marvel, she tended not to worry about the long-term trajectories for characters and encouraged the young actors she cast to do the same: “When you start to look at the comics, it can quickly get very confusing,” she noted. “I learned to really key into the director’s vision for the project and to try to understand their approach and the story they want to tell.”

The casting of Downey set the terms for the Marvel audition process: in nearly all cases, the studio valued screen tests over reputation. When casting a role, Finn would typically bring in top choices for an audition with a small camera crew, the core Marvel Studios producers, and (ideally) the movie’s director. The first round was the reading of a scene (known in industry parlance as “sides”), either in person or, if the actor wasn’t in Los Angeles, on tape. Further testing could involve new sides to showcase different aspects of the character, another actor to test potential chemistry, and even costumes or sets to see how natural the performer looked in a world of superheroes.

In the name of continuity, Marvel Studios revived another practice from the old Hollywood system: signing actors to long-term contracts, typically for nine movies. While the immediate justification was that Marvel needed its superheroes on call for crossovers and team-ups, the underlying motivation was financial. After Downey used the success of Iron Man to negotiate gargantuan paydays, Marvel Studios wanted the cost certainty of young talent locked into affordable multiyear deals. (That was another reason Finn didn’t focus on the biggest possible name for each role.)

Finn’s challenge with Thor was finding “an actor who could play Asgardian, which we equated to Shakespearean, almost, and yet be completely earthbound and relatable.” Back in 2004, when Avi Arad had almost set up a Thor movie at Sony, the leading contender for the role had been Daniel Craig. He still seemed like a strong candidate, but Craig quickly declined because he had committed to the James Bond franchise. Other actors Marvel seriously considered included Charlie Hunnam (Sons of Anarchy), Joel Kinnaman (a Swedish actor then largely unknown in the US), Tom Hiddleston (a British actor also little known in the US), Alexander Skarsgård (True Blood), and Liam Hemsworth (an Australian actor and another unknown). The guiding principle, according to Branagh: “Don’t let it be like Fabio.”

For any foreign actor trying to break into Hollywood, proper representation was key. Liam Hemsworth was handled by ROAR Management, whose cofounder William Ward had discovered him and his brother Chris when scouting for talent in Australia. Both Hemsworths were TV actors with greater aspirations. Ward had already flown Chris Hemsworth out to Hollywood and landed him an agent, Ilene Feldman, who had helped him get cast in the 2009 J. J. Abrams reboot of Star Trek. In a memorable opening sequence, Hemsworth played the brave but doomed father of Captain Kirk.

Chris Hemsworth had short brown hair, a clean-shaven face, and a Starfleet-slick American accent. Marvel Studios let him read for Thor but passed. Soon after, he went to Vancouver to shoot the horror movie Cabin in the Woods. Director Drew Goddard and producer Joss Whedon, who had encouraged him to pursue Thor, saw trade-magazine articles about the top contenders for the role and couldn’t help but notice that Chris wasn’t among them. “Why aren’t you in the mix here?” they asked. “What happened?”

“I don’t know,” he told them. “I blew my audition, I guess.”

Spurred on by Goddard and Whedon, and fueled by sibling rivalry—“frustration that my little brother had gotten further than me,” he said—he agitated for a second chance. (Liam had gotten far enough into the audition process that he did one round of Thor tests in a borrowed Pepper Potts wig.) Chris shot a new set of sides in a Vancouver hotel room, with his mother reading Odin’s lines, and many at Marvel suddenly saw the appeal. “When he came in for a screen test and told a story of Thor’s exploits,” Branagh said, “he did it with such relish, such fun, a sense of danger. He was able to occupy the character of Thor in a way that seemed just right to us.”

Finn, Feige, and Branagh didn’t want to lose Tom Hiddleston, who had originally gone on tape for Thor, but came back to audition for Loki, Thor’s conniving brother. Branagh had previously worked with Hiddleston on the detective series Wallander, and Feige, having seen the actor in a production of Chekhov’s Ivanov at Wyndham’s Theatre in London, agreed with the director that Hiddleston had the range to play a role that Marvel had big plans for. Stentz said, “The singular mandate above all other mandates was that they wanted Loki to be the villain for The Avengers. They literally said, ‘If you fail at everything else, please just give us a villain as good as Magneto in Loki.’”

Chris Hemsworth speaks to director Kenneth Barnagh.
Chris Hemsworth speaks to director Kenneth Barnagh.By MARVEL STUDIOS / Alamy.

Meeting at the Marvel Studios headquarters on a Saturday morning in May 2009, the Thor team made the final decision: Chris Hemsworth as Thor and Hiddleston as Loki. Feige anxiously paced around the conference table. “These will be the most important calls you make,” he warned Branagh. The director was confident in his choices, although he had no way of knowing just how much chemistry the two actors would have.

The shadow that Chris Hemsworth cast was about to get much bigger. “If you remember,” Stenz said, “when they announced Hemsworth, it was like, ‘Who? Captain Kirk’s dad? This skinny Australian surfer?’ The thing with Branagh is, he just has a freaking unparalleled eye for casting. He’s so good at it. That’s what we would tell people: ‘If Ken says he’s the guy, then he’s the guy.’ Indeed, he saw things in Hemsworth that I think not a lot of people had until that point. With these superhero movies, I think casting is seventy- five percent of it right there. You put the right actor in the role—as opposed to the almost-right actor—and it’s magic.”

Hemsworth immediately accepted the role, signing a multipicture deal. Whedon and Goddard had given him a collection of The Ultimates so he could get a handle on Thor. “I had read the comics,” Hemsworth said, “and this guy’s like 500 pounds.”

Branagh advised him that he should get “as big as he can,” so Hemsworth threw himself into a rigorous workout regimen to add lean body tissue. He already looked athletic, but the goal was to make him look godlike. Working with celebrity trainer Duffy Gaver, Hemsworth put on over twenty pounds of muscle in eight months. During that time, he also starred in the remake of Red Dawn, training with heavy weights several times a day when he wasn’t on camera.

After that shoot, he returned for a final costume fitting as Thor: “Within a couple of minutes, my hands started going numb,” Hemsworth said, “and everyone was like, ‘Yeah, that’s not cool.’ ” The measurements taken for his costumes only three weeks earlier were already so far off from his actual dimensions that the armor made to accentuate his muscles was instead cutting off his circulation. Branagh told the actor he was officially “big enough.” Hemsworth shifted away from eating a lot of calories and training with high weight and embraced a kettlebell workout that maintained his muscle mass instead of building it.

Casting Thor was difficult because he was a god; casting Captain America was difficult because he had to embody old-fashioned American decency without being corny. “When I was casting Captain America,” Finn said, “I did not understand where this was going to go—I really had no idea. When Kevin was first talking about The Avengers, that was mind-blowing to me.”

With Thor and Loki, Marvel Studios had, through a mixture of skill and luck, gotten things exactly right with a pair of obscure actors. It was willing to look at some marginally better-known names to play Steve Rogers. “We knew the central core of qualities we were looking for,” Finn said, “but the property was not well-known. People didn’t get it, it seemed a bit ‘B,’ it seemed a bit dated.” Ryan Philippe auditioned, as did Garrett Hedlund, Jensen Ackles, Chace Crawford, and (on a break from The Office) John Krasinski. Some of the finalists, including Krasinski, were brought in for screen tests that included dressing up in a Captain America costume on a period set. Krasinski, who would eventually appear in Doctor Strange in the Multiverse of Madness as the rubber-limbed superhero Reed Richards, later told the story of being half-dressed when a pumped-up Chris Hemsworth walked by in his full Thor costume. Krasinski regarded his own shirtless body and concluded that maybe he wasn’t actually cut out for playing an Adonis.

Some of the other actors who auditioned for Captain America also ended up in the MCU with different roles. Wyatt Russell, son of Kurt Russell and Goldie Hawn, had his first-ever professional audition with Sarah Halley Finn. A decade later, he would finally get to carry Captain America’s shield as John Walker (aka U.S. Agent) in the Disney Plus series The Falcon and the Winter Soldier.

Sebastian Stan also read for Steve Rogers. “But we saw something there that was a bit darker, a bit edgier,” Finn said. “And as we continued to go through the process, it seemed like the best role might be Bucky.” Captain America’s sidekick Bucky Barnes had been one of the rare Marvel characters who died and stayed dead. In the comic books, he expired heroically at the end of World War II and remained deceased for five decades before writer Ed Brubaker came up with the plotline that revived him as the brainwashed Russian assassin called the Winter Soldier. It wasn’t going to take Marvel Studios fifty years to turn Bucky into the Winter Soldier. Stan signed a nine- picture deal, which, for fans who kept up on Hollywood contract news, slightly undercut Bucky’s apparent death in Captain America: The First Avenger.

Also reading sides for Captain America was Parks and Recreation cast member Chris Pratt. Finn was intrigued by the actor but decided “it wasn’t quite a fit.”

“Casting Captain America was super hard and it took a long time,” Feige said. “I started to think, ‘Are we not going to be able to find Captain America, and if we can’t get Captain America, what are we going to do with Avengers? Is the whole thing going to fall apart?’ ”

There was one performer the studio really wanted, but early on, he had declined even to audition. Chris Evans had already played a Marvel superhero, the cocky Johnny Storm, also known as the Human Torch, in the two Fantastic Four movies directed by Tim Story for Fox. Finn was very familiar with his work. “My oldest two boys and I had seen Fantastic Four maybe 50 or 60 times,” she said. “We kind of went round and round and came back to Chris.”

Chris Evans Hayley Atwell and Joe Johnston on the set of Captain America The First Avenger.
Chris Evans, Hayley Atwell, and Joe Johnston on the set of Captain America, The First Avenger.From Moviestore Collection Ltd / Alamy.

There were many reasons Evans seemed perfect for the role, Finn said. “He was American. We’ve cast a lot of Brits, but we wanted to cast an American. And a great actor and funny and charming and affable and all of that. But then beyond the obvious qualities, I think there were the other ones that were a little harder to discern: his humility, the sense that he had a moral compass, that he was very relatable. He has this vulnerability as well as strength, so we could take him from skinny Steve to Captain America.”

Marvel Studios invited Evans to a meeting. “Bringing him in, showing him the artwork, showing him what was happening in this movie,” Feige recalled. They offered him a nine-movie deal for Steve Rogers, no audition required. “He took a weekend to decide,” Feige said. “That weekend was tough.”

Evans made his decision and, once again, the answer was no. “Getting the offer felt, to me, like the epitome of temptation,” the actor explained. “The ultimate job offer, on the biggest scale. I’m supposed to say no to this thing. It felt like the right thing to do. You see the pictures, and you see the costumes, and it’s cool. But I’d now woken up the day after saying no and felt good—twice.”

Evans added, “I like my privacy. The good thing about movies is there’s a lot of freedom built in: you make a film and then you have time off. If one of those films hits and changes your life, you have the opportunity to . . . run away. If you want to. Take some time, reassess, and regroup.” But if Captain America: The First Avenger was a hit, Evans knew he wouldn’t have that opportunity, because he would be playing Steve Rogers again right away.

Robert Downey Jr. called Evans and encouraged him to take the role, telling him that the fame that came with it would expand his opportunities as an actor, not constrict them. To entice Evans, Marvel Studios rolled back his commitment to just six movies: a trilogy of Captain America movies and three Avengers films. Evans would still be locked into the role for roughly a decade, which scared him. But sometimes, he decided, “maybe the thing you’re most scared of is actually the thing you should do.” He took the part.

Marvel announced the casting decision in April 2010, but it took years for Evans to quell his worries. He later confessed to being roiled by fear and self-hatred while making his first Captain America movie. The mantra playing in his head: “This is it. I just signed my death warrant; my life’s over. I can’t believe I did this. This isn’t the career I wanted.” He relaxed once he realized that the Captain America movies were actually good. “The biggest thing I was worried about was making shitty fucking movies,” he said. “I don’t want to make shitty movies and be contractually obligated to make garbage.”

Evans, too, embarked on an intensive effort to remake his body, one similar to Hemsworth’s, centered on a couple of hours of daily high-weight training. For Evans the most challenging aspect of the program was the high caloric intake. “Just eating all the time,” he complained. “You think it sounds nice, but it’s not, like, cheeseburgers. You have to eat these bland, naked pieces of chicken and rice. You’re just so full—it’s a pretty uncomfortable feeling.” Evans committed to the program, though, with impressive results.

Finn said she didn’t have any profound insight into which actors would be able to make the accelerated physical transformations necessary to become superheroes. “Fortunately, that is not my job,” she said. “My job is to find the embodiment of the character. Their [physical appearance is] somebody else’s job. But I would say that informs the process, right? There has to be a willingness to submit to the kind of intense rigors that it requires of you.”

She remembered her first meeting with Hayley Atwell to discuss the role of Peggy Carter, the superspy who would develop a relationship with Captain America, and the actress, “in her most perfect British accent, saying she was tired of period pieces, and she really wanted to kick some ass. And then she worked very, very hard. So knowing they have that willingness is great, but it’s never been a requirement. It’s been about ‘Let’s find the person who makes this character come to life.’ ”

Finn identified the casting of another Chris as her proudest moment in her long career at Marvel: she realized that Chris Pratt could play Star-Lord in Guardians of the Galaxy, the 2014 movie directed by James Gunn about a gang of reluctantly heroic outer-space misfits. Pratt was famous as the dimwitted goofball Andy Dwyer on the NBC sitcom Parks and Recreation, but Finn remembered the spark he had shown in his audition for Captain America years earlier: “I was so excited, and I went to James [Gunn], and he said, ‘Chris Pratt, no way, he’s totally wrong.’ ”

Finn secretly kept Pratt on the short list for Star-Lord while casting the rest of the Guardians ensemble. She saw Chadwick Boseman for the role of Drax and Lupita Nyong’o for Gamora, and although both parts went to other people (Dave Bautista and Zoe Saldaña, respectively), each actor made enough of an impression to get a leading role in Black Panther years later. Another example of slow-burn casting was the Scottish actress Karen Gillan, who had auditioned for Sharon Carter (a secret agent and Peggy Carter’s niece) in Captain America: The Winter Soldier. The role went to Emily VanCamp, but Finn realized the actress would be a perfect fit for Gamora’s sister Nebula, because she had a cherubic look even when she was projecting menace.

Star-Lord remained uncast, so Finn prevailed on Gunn to at least let Pratt do a screen test for the role (remembering well how that had helped showcase Downey as a good fit for Tony Stark). Pratt was intrigued, if skeptical that he was actually the right man for the job. But his screen test was the type of moment casting directors dream of: “Chris walked in the room, and we have this audition, and it’s really magical. Within ten seconds, James turned around and looked at me and said, ‘He’s the guy.’ ”

Pratt had further to go to achieve a superhero’s body than the first two Chrises. He had intentionally gained weight to make his Parks and Recreation character appear more “schlubby.” Marvel called Duffy Gaver, the trainer who had worked with Hemsworth. “I got a phone call and they wanted to see if I was available to train Chris Pratt. They said he’d just walked out of their office and found out he was the lead in their next franchise,” Gaver remembered. He quickly Googled Pratt and agreed to do it. “I think Chris’s body at the time was working for the type of actor he was, but it was time for a change.”

Twenty minutes later, Gaver was on the phone with Pratt. They met for coffee the next day and began training the day after that. “Chris was very prepared to put the work in,” Gaver said. Although Finn insisted that she didn’t vet actors on the basis of how devoted they were to workout regimes, Gaver could only judge by the people who Marvel sent his way, and he could infer that at some point in the process, actors who didn’t demonstrate the necessary level of commitment were getting screened out. “Marvel is hiring people for years and years, so they want people who are very dedicated and disciplined. The people I get called to train have already passed quite a litmus test to arrive where they are.”

Gaver used Pratt as an example for his other clients, telling them how the whole gym would pay attention to him during his workout. “Not because he was a movie star, because at the time he wasn’t,” the trainer said. “He’s dripping sweat, out of breath. He was just a guy who was killing himself in the gym.”

Marvel also introduced Pratt to nutritionist Philip Goglia, who increased Pratt’s caloric intake to 4,000 a day, plus one ounce of water for each pound the actor weighed. “I was peeing all day long, every day,” Pratt said. “That part was a nightmare.”

Within six months, Pratt had sculpted himself into a superhero. The writers of Parks and Recreation had written a scene for season seven where his character, Andy Dwyer, needed to take his shirt off. “We realized we couldn’t do it,” said showrunner Michael Schur. “Andy is not a guy who has a perfectly constructed human form with ripped abs and gigantic biceps.”

On Instagram, Pratt posted a shirtless selfie of himself captioned “Six months, no beer.” It was the first selfie of a Marvel star to go viral, as the world gaped at his physical transformation. Throughout its history, Hollywood has sold the female body to moviegoers, and young actresses have starved and surgically altered themselves to achieve impossible ideals. Marvel Studios didn’t make the first movies that emphasized the male body, but in presenting one chiseled superhero after another in blockbuster after blockbuster, it created a world in which the male form is as malleable as the female form—and presented just as routinely as the object of fantasy. Like Dr. Abraham Erskine with his Super Soldier serum, Marvel Studios decided that it could make its own superior specimens of humanity and benefit from the results.

Superpowers, not being real, could work any way the creators of comic books and comic-book movies want: it’s an extremely literal choice to say that with great power comes great muscularity. But Marvel leaned into that genre convention, so much so that the actors who didn’t have rippling physiques felt the need to bulk up. Sebastian Stan admitted that when he arrived on the set of Captain America: Civil War, “I was so insecure being around these massive fucking guys so I started lifting really heavy and ate a lot. I remember I showed up, and I was a little bit bigger than I had been in The Winter Soldier. The [fake prosthetic] arm was a bit tight—I was losing circulation.”

Although Robert Downey Jr.’s torso was typically concealed on-screen by a tailored suit or CGI armor, being in a superhero movie spurred him to remake his body too. He was already doing yoga and martial arts and weight training, but he started adding muscle: “I feel like I got a five-to-seven-year window and then if it goes past that, I’m sure all the optical stuff and CGI will have advanced to make you look better.”

Chadwick Boseman, star of Black Panther, said that his Marvel workouts never stopped. “Even if you change the regimen—say, you have to get smaller for another role and you have to beef up again for this—there are certain things you have to keep doing.”

Paul Rudd, like Pratt known as a comic actor, got in shape to play Ant-Man. “It’s probably changed my life,” Rudd said of his Marvel fitness regimen. “It’s completely changed the way I eat food and work out. Fitness and diet have become something at the forefront of my life: that was never the case.” Rudd planned to keep up the routine, to maintain both his viability as a movie star and his own well- being. “I feel way better,” he admitted. “I owe the franchise maybe a few extra years of life.”

Perhaps the most eye-popping Marvel transition of all belongs to comedian Kumail Nanjiani, who, after years of playing cuddly nerds, revealed his Eternals-ready muscles in 2019. “I will keep those opinions to myself,” another comedian and Marvel actor said with a laugh when asked about Nanjiani’s new physique. “He is very . . . ripped. He is extraordinarily ripped.”

Michael B Jordan and Chadwick Boseman in Black Panther 2018.
Michael B Jordan and Chadwick Boseman in Black Panther, 2018.By MARVEL STUDIOS/WALT DISNEY PICTURES/Alamy.

Some methods of bulking up go beyond weight training and diet. Though forbidden by sports leagues, many steroid treatments are perfectly legal. Dr. Todd Schroeder, associate professor of clinical physical therapy and director of the University of Southern California Clinical Exercise Research Center at the USC Division of Biokinesiology and Physical Therapy, estimated that over half of Marvel’s stars use some form of performance enhancing drug (PED) to get the physiques they want. “At least for the short term,” he said. “I would say that fifty to seventy-five percent do.” For an in-depth 2013 investigation into the industry’s most popular performance- enhancing drug, human growth hormone (HGH), the Hollywood Reporter interviewed a number of talent agents and managers who considered PED use the “worst-kept” secret in Hollywood—just as commonplace, perhaps, as Botox and Restylane.

As Dr. Schroeder observed, “Nowadays, it’s kind of expected and, working under a doctor’s care, it’s really been accepted. A lot of actors won’t talk about it openly, but they will work with a physician as well as a nutritionist and a trainer, and it’s a team. It’s not smart for an actor to do that alone. The big thing is, you can take steroids, testosterone, different androgens, growth hormone for a short period of time without any lasting effects on the body. It’s not like you become addicted to it.” Except, potentially, Dr. Schroeder noted, psychologically. If an actor loves the new shape of his body, and how people react to it, he might feel compelled to keep it.

A peak Marvel physique, however, isn’t something that one can sustain indefinitely. “Especially as you get older,” Dr. Schroeder said. “Like Robert Downey Jr., all the Iron Man [movies] he’s done, and some of them he’s gotten in really good shape for, but maintaining that is challenging. It’s a tough, tough world out there. What people expect of you and how you need to look, and trying to maintain that. I feel for these actors, especially if you’re in a Marvel role, where you’re going to be in multiple films.”

Robert Downey Jr. and producerMarvel president Kevin Feige on the set of Iron Man 2.”
Robert Downey Jr. and producer/Marvel president Kevin Feige on the set of Iron Man 2.”From PictureLux / The Hollywood Archive / Alamy.

There’s also the strain of trying to have a Marvel career while simultaneously looking less-than-super for other roles. Aaron Williamson, one of Hollywood’s top trainers, has worked as a trainer and consultant for films like The Fantastic Four, G.I. Joe Retaliation, Terminator Genisys, and Neighbors. “Actors are trying to get on camera and blow everyone away,” Williamson said. “Everyone’s just maxed out, doing everything possible to look superhuman. . . . Someone might do a film where they have to look like a ‘normal’ person and then for their next project, they’ve got to look like this bulked-up, crazy-looking superhero guy. It’s impossible to go from one extreme to the other overnight without some type of help.”

“There’s long-term health concerns, but short-term, there really isn’t,” Dr. Schroeder said. “So if you’re preparing for a role, and you’re going to get paid ten million dollars to look a certain way for a role? Then why wouldn’t you do it under a doctor’s care? Take some things that aren’t natural but will change your body to look the way they want it to look, and gets you the recognition?”

Dr. Schroeder emphasized that he was speaking from his own expertise and observation, not firsthand treatment of the Marvel stars. About Chris Hemsworth, he said: “He’s always been in really good shape. His family, his genetics—they all, if they work out a little bit, they get in really good shape, and so he’s taken it to the next level. A lot of people say, ‘Oh, he does steroids, for sure.’ And my opinion? I would say, ‘No, he does not.’ ”

Marvel Studios didn’t have to cast movie stars or even people in particularly good shape. Instead, like the toy company it still was, it simply made its own action heroes.

CORRECTION: This story has been updated to reflect that, each day, Chris Pratt’s nutritionist gave him one ounce of water for every pound he weighed—not one glass, as previously stated. 

Excerpted from MCU: The Reign of Marvel Studios by Joanna Robinson, Dave Gonzales, and Gavin Edwards. Copyright (c) 2024 by On Your Left, LLC. Used with permission of the publisher, Liveright Publishing Corporation, a division of W. W. Norton & Company, Inc. All rights reserved.