In a speech at the University of Southern California's graduation ceremony, Kevin Feige, President of Marvel Studios, revealed that Clive Owen almost played Tony Stark in the 2008 film Iron Man before the role was given to Robert Downey Jr. Feige described how the success of the film and the future of the studio rested on finding the right actor to play Iron Man, and Owen had turned down the role.
However, Downey's portrayal proved to be a huge hit, leading to his involvement in ten MCU movies and establishing the biggest interconnected universe in cinematic history. Feige concluded his speech by stating that not getting your first choice can often be the greatest thing that can happen to you.