Robert Downey Jr. and Gwyneth Paltrow‘s banter made it into Iron Man!

Jon Favreau spoke to People about the two actors, and how their real-life conversations actually made it into the Marvel movie as conversations between their characters, Tony Stark and Pepper Potts.

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“I was a very good student where I would take notes as they would talk, and whether it was improvising or even just talking about the scene, I would write stuff down that they would say,” he said.

He remembered a moment Gwyneth actually corrected Robert “because we were reading the script and it said, ‘This looks like Jackson Pollock’s spring period.’ And then she corrected us in rehearsal. She says, ‘No, it’s actually The Springs period. The Springs is the part of the Hamptons where Jackson Pollock lived and worked, not spring, not the season.’”

“So I wrote down every word, and she’s correcting him in the movie when he says, ‘the spring period.’ So it just adds to their sort of nippy banter. I find it thoroughly compelling and entertaining to watch the two of them on screen together because they had this banter that has an edge to it,” he continued.

The two went on to reprise their roles in additional stand-alone Iron Man films as well as other Marvel projects before their last appearances as Tony Stark and Pepper Potts, respectively, in 2019’s Avengers: Endgame.

“They complement each other so well. They’re so different, but yet [have] so much mutual respect and admiration. I love that,” he added.

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