Robert Downey Jr.'s "Iron Man" became one of the most admired characters in the film industry. But it has been revealed that RDJ almost failed to land in this big break.

The Marvel Cinematic Universe is indeed one of the most successful franchises in history. To look back, they began the journey of the Avengers in 2008 through the first "Iron Man" film.

Since the birth of Phase 1, RDJ -- who was once a controversial choice for the role of Tony Stark -- became an icon as he stood there as the father of all the MCU superheroes. He then joined the list of the pioneers and original actors of the franchise.

However, Marvel Studios almost took a different route since the 54-year-old actor was not their first choice -- not even their second nor third!

It is a given that nobody would have been perfect enough for the role other than RDJ. But still, here are some of the actors who could have made it instead of the original Mr. Tony Stark actor.

Tom Cruise

The "Mission Impossible" actor became the first and original choice to play the role of "Iron Man." But in the end, he failed to reach an agreement with the team, as Cruise wanted to make a few changes with the script.

In the same year when the first "Iron Man" was released, the 57-year-old actor came out and recalled the time when he almost bagged the role.

"Not close, and I love Robert Downey Jr. I can't imagine anyone else in that role, and I think it's perfect for him," he said in his exclusive interview with ComicBook.com in 2008.

Sam Rockwell

After failing with Cruise, Marvel continued searching for another potential actors and bumped into Sam Rockwell.

In his interview with The A.V. Club years ago, Rockwell revealed that he was up to portray the role of Tony Stark in the franchise's early development. In fact, Jon Favreau, the director of the first MCU film, reportedly approached him for screen testing as the billionaire philanthropist.

Though it did not work out for him either, he eventually came back in "Iron Man 2" as Justin Hammer.

Hugh Jackman

The 51-year-old actor is most famous for his role in the 2000 film "X-Men" and through his seventh and last film "Logan" in 2017. He currently holds the Guinness World Record for "longest career as a live-action Marvel superhero."

But according to CBR, Jackman was also considered for the role way before RDJ. Had he accepted the role, he could not have won the acknowledgment from Guinness!

Nicolas Cage

The actor, who also underwent a screen test for Superman, expressed his intention to take the role of Tony Stark a decade before it has been released.

According to ScreenCrush, the 56-year-old "National Treasure" star failed to get both Man of Steel's title and Iron Man's suit in the end.

But still, he landed on several superhero roles, including Johnny Blaze in the 2007 film "Ghost Rider" and Big Daddy in "Kick Ass."

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