Christopher Nolan says Robert Downey Jr. as Iron Man is one of the most important casting decisions "in the history of the movie business"

It's no secret that the MCU has been a cultural juggernaut since its inception in 2008 (even if its influence seems to be on the wane amid a touch of superhero fatigue), and the de facto face of the cinematic universe has always been Robert Downey Jr.'s Iron Man. 

It shouldn't come as a huge shock, then, that Christopher Nolan – who himself made some genre defining superhero flicks with the Dark Knight trilogy – thinks Downey Jr.'s Iron Man is one of cinema's key casting decisions. 

"He has such charisma as Tony Stark," Nolan told Stephen Colbert. "I think him playing Iron Man is one of the most consequential casting decisions that's ever been made in the history of the movie business. And I wanted to give him the opportunity to lose himself in a part, lose himself in another human being the way that great actors love to."

Nolan recently teamed with the actor for Oppenheimer, with Downey Jr. portraying Lewis Strauss.

Downey Jr. is up for the Best Supporting Actor Oscar for his role, while Cillian Murphy is nominated for Best Actor. The film is also in the running for Best Picture, and Nolan is up for Best Director (see the full list of 2024 Oscars nominations through the link). 

Next up for the MCU is Deadpool 3, which hits theaters this July 26. It's the only MCU movie coming this year after a slew of delays. 

You can keep up to date with everything the MCU has in store with our guide to all the upcoming Marvel movies and TV shows.