[Robert Downey Jr.] is Iron Man. He is Iron Man in the way that Sean Connery was James Bond. I have no intention of making Avengers 2 without him, nor do I think I’ll be called upon to do that … I loved working with Robert, and everybody knows he embodied that role in a way no one else can. The day he was cast, I went up to [Marvel Studios president] Kevin Feige and said, “You brilliant son of a bitch.
Joss Whedon, June 5, 2013 on The Daily Beast (x)
“I have no intention of making Avengers 2 without him”