After working with Robert Downey Jr. on Oppenheimer, director Christopher Nolan praised Marvel Studios for casting him as Iron Man when they kicked off the Marvel Cinematic Universe.

Nolan went as far as calling Downey Jr.'s casting as Tony Stark/Iron Man one of the greatest decisions in the history of movies. He also praised Jon Favreau, who directed the movie, for his insight in casting Downey as the titular character.

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While talking with Josh Horowitz on the Happy Sad Podcast, Nolan praised Downey and Iron Man director Favreau for realizing that Downey was the right choice to play the now iconic superhero. "When Favreau had the insight to cast him as Iron Man, it's one of the greatest casting decisions in the history of movies," Nolan said. "You look at what that did and where that went with everything. I think that was Jon just knowing what an incredible actor, what an incredible potential that was from Downey."

Nolan praising the casting for Downey has even more merit knowing that Iron Man was released not too long before the release of Nolan's The Dark Knight in 2008. The Dark Knight was a followup to the critically acclaimed Batman Begins that was also primed to feature Batman's most iconic villain, The Joker, so it was widely expected to be a hit at the time. Iron Man, by contrast, was a hero that not many were familiar with before the film, which played a part in why it was such a surprise hit. And doing so started the revolution of the MCU in the years following.

It may seem like a distant memory now, but Downey Jr.'s performance as Iron Man fueled his miraculous Hollywood comeback in 2008. Before that, Downey had a reputation for being the Hollywood bad boy in the 1990s due to his rampant drug use, which effectively destroyed his career despite his obvious talent. Downey had attempted to get back into the limelight when he starred in well-received films like Kiss Kiss Bang Bang or played minor roles in biopics like Good Night and Good Luck after he became sober, but they didn't raise his stock. Playing Stark gave him a second chance to establish himself as a leading man again, which led to his iconic performances in the films like Tropic Thunder and Sherlock Holmes. It all started with his fresh take on being a superhero in Iron Man.

And now, he gets to star in movies that allow him to stretch his legs as an actor. Downey's performance in Oppenheimer is garnering plenty of praise to the point where he may be nominated for an Academy Award. That's happened only twice before in his career, being nominated for Best Supporting Actor in Tropic Thunder in 2008 and winning Best Actor in Chaplin in 1992. With him now done with the MCU, fans may see the very best in Downey's acting abilities from here on out.

Oppenheimer is now playing in theaters, and Iron Man is available on Disney Plus.

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Source: Josh Horowitz/YouTube