AR: Joe and I always say Robert is the hardest-working actor we've ever encountered. He is very dedicated to his craft and puts an enormous amount of his psychic energy into his performance. As you can imagine, this character is as much of an iconic experience for him as it is for anybody in the [audience]. That shot where he says “I am Iron Man” and snaps his fingers was the very last shot of the entire movie. We shot that back in January [during the final reshoots] and we all walked away from the movie after he performed that moment.

Source: Los Angeles Times May 03, 2019 19:34 UTC