Robert Downey Jr. Rejected An Oscar-Winning Sci-Fi Movie After Iron Man

Alfonso Cuarón's "Gravity" is not only one of the sci-fi movies Neil deGrasse Tyson approves of, but also a massive success with general audiences. It had seven Oscar wins out of 10 nominations, including Best Director, Cinematography, and Visual Effects, and nearly $725 million at the box office (via Box Office Mojo). The movie tells the story of two astronauts who are hit by debris while on a mission, and they must find a way to survive and return to Earth. Sandra Bullock (Ryan Stone) and George Clooney (Matt Kowalski) are the stars of the film. But initially, Cuarón had a different duo in mind for his movie.

Robert Downey Jr. was originally invited to star in "Gravity" with Angelina Jolie. While "Gravity" premiered on August 28, 2013, Cuarón shot the movie in 2011. Around the same time, Marvel was filming "The Avengers," Marvel Cinematic Universe's first big crossover movie. Robert Downey Jr. had a major role in it after becoming the image of the still-young MCU in "Iron Man" (2008), the film that kick-started Marvel's universe, with RDJ's performance being a key element of that success. The sequel, "Iron Man 2," premiered in 2010, a year before the production of "Gravity" started. 

The actor would have had to juggle both Cuarón's movie and the first "Avengers" adventure if all parties had agreed to him filming both at the same time. But the conflicting schedule wasn't the main reason Downey Jr. passed on playing Matt Kowalski. The actor explained in an interview for The Howard Stern Show, years after the "Gravity" release, that the issue was the constraints of filming the space movie the way Cuarón envisioned it.

"Everybody winds up doing what they're supposed to do, and sometimes, someone gets in a motorcycle accident, and then the person who winds up doing the part [kills it], and you say, 'I couldn't have imagined anyone else there,'" RDJ told Stern in an interview in October 2022. He explained that he came on early in the project, even before Jolie was cast to star in the movie. He hit it off with Cuarón and liked the idea. Stern mentioned Downey Jr. had already revealed he couldn't work in the confined spaces the "Gravity" sets required him to. That's when the actor detailed the shooting experiences that Cuarón needed, and he wasn't comfortable with.

"What I can tell you is I went to do a test with a new sort of multi-spherical camera thing they were doing for how they were going to do all the CGI," RDJ recalled. "I'm one of those guys who can be comfortably uncomfortable pretty easily. I went in the morning to do that, and we did it for about 20 minutes. I said, 'This is crazy, how much longer?' They go, 'It's like another two to four hours.' I said, 'No, it isn't!'" The actor added that "You've got to have boundaries. You've got to leave before you flip out," suggesting claustrophobia may have been a major factor in his quitting the sci-fi film.

Separately, Cuarón had told The Hollywood Reporter a similar story in 2014, addressing Downey Jr.'s exit from the picture, though the director did not provide as much context as the actor did in his chat with Stern. "It became very clear that, as we started to nail the technology, or narrow the technology, that was going to be a big obstacle for his performance," the director said. "I think Robert is fantastic if you give him the freedom to completely breathe and improvise and change stuff. [But] we tried one of these technologies, and it was not compatible. And, after that, we [had a] week that we pretended as if nothing was happening, and then we talked and said, 'This is not going to work. This is tough.'"

Stern asked RDJ if he would have done the movie had he known that "Gravity" would become huge and that he would make the $70 million Clooney made, but the actor stuck to his decision. "Any of us can have anything, but we can't have everything," RDJ concluded. 

Bullock was nominated for Best Actress, eventually losing to Cate Blanchett ("Blue Jasmine"), while Clooney wasn't nominated for Best Actor. After skipping on "Gravity," Downey Jr. went on to star in multiple MCU blockbusters, including several "Avengers" sequels. He will still be featured in upcoming films, such as "Avengers: Doomsday," which he agreed to star in, and "Avengers: Secret Wars" in late 2027. Outside of Marvel movies, RDJ won his first Oscar in 2024 for his supporting role in Christopher Nolan's "Oppenheimer." Previously, RDJ was nominated for "Chaplin" (1993) and "Tropic Thunder" (2009).