Robert Downey Jr.’s casting as Iron Man was a big risk for Marvel, as his career was struggling at the time. His performance set the tone for the entire MCU and influenced the decision to cast big names in future films.
The casting choices for Iron Man and other characters could have drastically changed the MCU. Tom Cruise, Timothy Olyphant, Hugh Jackman, and Nicolas Cage were considered for the role, and Rachel McAdams was offered the role of Pepper Potts.
Quentin Tarantino was considered to direct Iron Man, which would have resulted in a very different film with his signature style. However, Jon Favreau ultimately helmed the project, leading to the success of the MCU as we know it today.

The film that kickstarted the entire Marvel Cinematic Universe, 2008’s Iron Man, was a breakout hit that narrowly avoided becoming an entirely different film. Robert Downey Jr.’s iconic performance as Tony Stark informed Marvel Studio’s sense of humor and character for the next decade to come. Without the success of Iron Man, considered a big gamble for an unproven movie division of a comic company, the MCU might not have manifested, changing the film industry forever.

Speculation about how Iron Man might’ve been so different is important because of just how impactful the film was. Some of Marvel’s original plans for the story of Tony Stark seem downright drastic changes in hindsight. These near-misses could’ve affected not only the final critical reception of the film, but the core characteristics of the MCU timeline going forward. As the foundation for the world’s most successful connected universe to-date, every little change made during filming had a massive butterfly effect on films to come.

Related: 10 Characters Who Can Replace Iron Man In The MCU

10 Tom Cruise Would’ve Made Iron Man More Star-Studded

Tom Cruise Was Almost Cast As Iron Man

Today, the success of his portrayal of Tony Stark has Robert Downey Jr.’s legacy as an unequivocal star set in stone. But what many younger fans of the character may not realize is how big of a risk Marvel took with his casting. At the time, Robert Downey Jr.’s career was in a rough spot, the 43-year-old actor struggling with a very public battle with drug addiction that culminated in his arrest.

Of the other actors Marvel had considered, Tom Cruise would’ve had the most significant effects on the greater cinematic universe. Had Cruise’s version of the character been as beloved, the MCU might’ve learned to find safety in stardom, relying more on big names that could draw audiences in rather than taking a chance on figures who – while they’re now big stars – were relative unknowns at the time, like Chris Hemsworth and Tom Hiddleston. Luckily, even Tom Cruise admits he couldn’t play Iron Man as well as Robert Downey Jr. did.

9 Iron Man’s Other Castings Would’ve Changed The Avengers

Nicolas Cage, Timothy Olyphant, & Hugh Jackman Were Considered For MCU’s Iron Man

Tom Cruise wasn’t the only contender for the role beyond Robert Downey Jr. Other contenders included Timothy Olyphant, coming off the success of the Deadwood TV series, and Hugh Jackman, already well-established as helming the X-Men films as Wolverine. Even Nicolas Cage was at one point attached to an older version of the project.

As the first Avenger to be cast, these alternate versions of Tony Stark might’ve resulted in a much stranger cast of Avengers, as It’s hard to imagine Chris Evans sharing the screen with the likes of Nicolas Cage. Tony Stark wasn’t the only character who’s casting would’ve affected the MCU at large, however. The role of Pepper Potts was offered to Rachel McAdams by director Jon Favreau, who was nervous at the time to commit to the yet-unproven superhero genre. McAdams eventually joined the MCU as Christine Palmer in Doctor Strange, meaning her playing Pepper would’ve opened up a spot for a different actress later on.

Quentin Tarantino Almost Directed Iron Man

While Robert Downey Jr. as Tony Stark may have been Marvel’s biggest gamble, director Jon Favreau wasn’t exactly a shoo-in for the project, either. When Iron Man was first getting off the ground, famed writer and director Quentin Tarantino was heavily considered. His signature style would’ve resulted in a much different film, likely including more intense violence, fast-paced, irreverent dialogue, and potentially some of his other distinctive quirks, such as the infamous trend of films including close-ups of feet.

Whatever Tarantino’s vision for Iron Man might’ve been, it’s undeniable that he would’ve imparted some heavy changes to the Marvel format going forward as an auteur. Before being in talks for Iron Man, Tarantino also expressed interest in directing a Luke Cage film. Yet despite his clear love of comic books, the iconic director has since become a vocal critic of the MCU’s effect on Hollywood, with Tarantino vowing to never direct a Marvel film.

MODOK Was Almost Iron Man’s First Villain

Before the mid-2000s, attempts at an Iron Man film had been considered before. Long prior to the inception of the MCU, the rights to a live-action Iron Man film were passed between Universal and Fox Studios during the 1990s like a hot potato. Fox opted to enlist Iron Man’s co-creator, Stan Lee, to write a script alongside Jeff Vintar, known now for I, Robot and Long Hello and Short Goodbye.

Compared to what fans got in 2008, this script pitted Tony Stark against MODOK, a giant, weaponized floating head and leader of Advanced Idea Mechanics, or A.I.M., a guild of evil engineers. This villain would’ve been a difficult choice to sell to audiences by the nature of his bizarre design, and the special effects available to Fox in 1996 would’ve probably struggled with rendering his massive square face. It wasn’t until 2023’s Ant-Man and the Wasp: Quantumania that the MCU would dare to include the character, despite being a relatively prolific villain in the comics.

6 The Mandarin Almost Put Magic In The MCU Right Away

Iron Man Almost Had The Official MCU Mandarin In It

Though the failed 90s script for Iron Man put MODOK in the spotlight, Jon Favreau’s original vision in 2008 also nearly included a different villain. In the comics, one of Iron Man’s most iconic villains had been the Mandarin, an evil sorcerer utilizing ten magical rings providing him various magical powers. Cutting the Mandarin was an extremely last-minute decision, with the crew of Iron Man reportedly hurrying to re-write Obadiah Stane as the villain instead.

Favreau ultimately decided that the Mandarin’s presence in the story would’ve felt too out-of-left field and disconnected from the story of Tony Stark. As a result, the concept of human-cast magic wouldn’t enter the MCU until 2016’s Doctor Strange, and the Mandarin wouldn’t make a true appearance until 2021’s Shang-Chi and the Legend of the Ten Rings. Obadiah Stane as the MCU’s villain could’ve been responsible for Marvel’s habit to make their villains simply an evil version of the hero, to mixed success.

Iron Man’s Final Scenes Were Massively Ad-Libbed

Part of Robert Downy Jr.’s success as Iron Man is his gifted ability to think on his feet, ad-libbing and improvising as scenes demanded it to contribute some impressive writing of his own to Marvel’s stories. This was especially helpful on the set of Iron Man, as the film frantically filmed while being re-written on the fly. But his most important improvised line had a powerful effect on the proceeding heroes of the MCU, cutting out a distinct characteristic superhero stories had become known for.

After the climax of the film, Tony Stark addresses a horde of reporters eager to make sense of the events that had transpired. Facing the media, he admits “the truth is… I am Iron Man“, confirming to the public his involvement without a shadow of a doubt. This iconic line was actually written on the fly by Robert Downey Jr., and as a result, Marvel films have tended to ignore the typical drama of maintaining a secret identity with most of its heroes, with only Spider-Man really being a glaring exception.

4 Sam Rockwell As Tony Stark Almost Left Al Pacino As Justin Hammer

Sam Rockwell Was Almost Iron Man 1’s Hero, Not The Sequel Villain

Rachel McAdams wasn’t the only actor considered for a role in Iron Man that went on to enter the MCU at a later date. Sam Rockwell was best known at the time for his roles in The Green Mile and Hitchhiker’s Guide To The Galaxy, demonstrating a healthy range of drama and comedy that made him a contender for Tony Stark. Ultimately, Rockwell’s lack of wider appeal made him a little too inaccessible to play the MCU’s flagship hero.

Had Rockwell been cast, it goes without saying that Tony Stark would be a very different character, and likely would’ve inherited Rockwell’s love of dancing in his films. Beyond that, if Sam Rockwell hadn’t been available, it’s likely that his casting as Justin Hammer in Iron Man 2 would’ve instead gone to Al Pacino, who was also considered for the character. As different as Justin Rockwell’s Tony Stark would’ve been, the thought of Al Pacino’s Justin Hammer conjures an extremely different, more serious villain from the goofy Justin Hammer fans got.

3 The Toughness Of A Car Changed MCU Fights Forever

Iron Man 1 Had Some Major Stunt Issues That Changed The Movie

Jon Favreau had some experience with fight scenes going into Iron Man. His work in 2005’s family-friendly action adventure film, Zathura: A Space Adventure, included some light action, and the iconic Santa fight in 2003’s Elf was a slapstick masterpiece. Yet the scale of the superhero film was a whole new level, and the difficulties of a certain stunt going into the final fight with Iron Monger changed how Marvel handled fight scenes going forward.

The climactic confrontation at the end of the film called for Tony Stark’s Audi R8 to be flipped over onto Obadiah Stane, who would then cut the vehicle in half. However, no matter how hard they tried, Favreau and his team were reportedly unable to get the car to flip. Impressed with the car’s safety, Favreau opted instead to redo the choreography of the fight, influencing Marvel to move away from street-level brawls and incorporate more high-flying action befitting of superheroes. Audis would appear in the MCU frequently going forward, as a testament to the impression the brand made.

2 Phil Coulson Was Almost Much Less Important

Iron Man Gave Phil Coulson A Way Bigger MCU Future

Having gone on to star in Agents of S.H.I.E.L.D. and featuring in one of the most emotionally-devastating death scenes in the MCU, it’s easy to forget that Agent Phil Coulson actually made his debut as early as Iron Man. However, Coulson was originally supposed to play a much more minor role in the film, having far fewer lines. Clark Gregg was cast as the S.H.I.E.L.D. agent, another relative unknown at the time, though certainly a working actor coming off of films like Hoot and In Good Company.

Favreau was reportedly so impressed with Gregg’s charisma as Agent Phil Coulson that he re-wrote the part to be more significant, giving him a healthy dose of extra screen time. Without this decision, Phil Coulson might not have even re-appeared, let alone starred in his own series. Had Favreau not re-written Coulson to be more significant, the seven-year run Agents of S.H.I.E.L.D. likely would’ve never existed, let alone the character’s appearances in Iron Man 2 and The Avengers.

Iron Man 1 Had Iron Man 2’s Previous Villain Plan

Though the Mandarin was to be the antagonist of Iron Man‘s original script, Obadiah Stane was always included. In the finished product, Stane begins the film as Stark Enterprises’ former CEO, jealous of Tony’s success in the role as Howard Stark’s successor. He goes on to betray Tony, leading to his increasing desperation and brief career as super villain Iron Monger. The original plan was for this to not fully transpire until Iron Man 2, with Stane presenting himself to Tony and the audience as a close friend and ally for the entire first film before finally betraying him in the sequel.

In the grand scheme of the MCU, Obadiah Stane was a somewhat forgettable antagonist. However, having him remain as a sort of sidekick to Tony Stark until his eventual betrayal in a later film would’ve made for a much more satisfying arc as a villain. The MCU would later go on to depict a similar, slower heel-turn into evildoing with Wanda’s transformation as The Scarlet Witch. Though the original trilogy of Iron Man films missed out on this opportunity, theories have been floated that speculate on Stane’s return to the MCU, meaning some of them could still be used in some form later down the line.

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 Iron Man 1 nearly founded a different MCU.  Read More