Robert Downey Jr. is the face of the Marvel Cinematic Universe. Even though he hasn't technically been a part of the MCU since 2019, RDJ is still closely associated with the multi-billion-dollar franchise. After all, he did technically help start it after starring in 2008's Iron Man. But, did you know that a different Marvel film had already been eyeing RDJ for a starring role years before Iron Man came out?

Jon Favreau, the director of the first Iron Man movie and the actor behind the fan-favorite MCU character, Harold "Happy" Hogan, recently revealed that RDJ was up for the role of Dr. Doom in the 2005 film, Fantastic Four.
This revelation came during a recent sitdown between Favreau and Marvel Studios president, Kevin Feige.
The video is a celebration of the 15th anniversary of the film that started it all for the MCU where the two pivotal figures discussed several things that led to the creation of the influential cinematic universe.
In the video, Favreau reveals that Downey Jr. would've played the role that ultimately went to Julian McMahon, the actor, who, at the time, was best known for Nip/Tuck. McMahon would go on to portray Dr. Doom in the two Fantastic Four movies. Chris Evans, another actor who later starred in the MCU, was part of the same pair of projects, playing the role of the fiery Fantastic Four member, Johnny Storm.
Of course, both Feige and Favreau are thankful that the role of Tony Stark ultimately went to Robert Downey Jr.
Signing RDJ to play Tony Stark is easily one of the best casting decisions in Hollywood history. He would go on to play the role of the eccentric genius, billionaire, playboy, and philanthropist to the T for a total of ten films in the MCU, including his last appearance in 2019 where he effectively ended things in Avengers: Endgame.
As of now, Downey Jr. has no plans to return to the MCU as Iron Man but this hasn't stopped the rumors that he's coming back soon, or at least his character.
RDJ most recently received a public offer from Vin Diesel to join the Fast and Furious universe as its final villain. It remains to be seen if he'll accept this or if the offer was even serious in the first place.
RDJ will star in Christopher Nolan's Oppenheimer alongside Cillian Murphy and Emily Blunt. The upcoming biographical thriller will premiere on July 21 and is expected to be Nolan's longest movie yet.