Robert Downey Jr. Calls 'Due Date' Director His 'Soul Mate'

'Iron Man' star calls Todd Phillips 'a genius,' while admitting to having heated arguments with the director.

Jon Favreau, Guy Ritchie, Oliver Stone — these are just some of the acclaimed directors that Robert Downey Jr. has collaborated with over the course of his lengthy career. But after 40 years in the business, RDJ says he finally met his filmmaking soul mate in the form of "Due Date" director Todd Phillips.

When the "Iron Man" and "Sherlock Holmes" star spoke with MTV News on the "Due Date" red carpet in New York City on Monday about his work on the new film, he showered Phillips with praise. "What happened was that I found my soul mate in the artistry of Todd Phillips," he declared. "He's a genius."

Downey suggested, however, that his respect for Phillips might not have been apparent had you seen the two on the set of "Due Date." The actor admitted that he and Phillips often got at each other's throats, but thankfully, that was all just part of the process.

"We would get together and have heated arguments," revealed Downey. "If we had taped them, you would have thought that we'd never speak to each other again."

But the by-product of these conflicts, said Downey, was the creation of some fully formed characters — namely, his role as the expectant father Peter and Zach Galifianakis' Ethan, an aspiring actor. "We made a character for [Galifianakis]," Downey explained, referring to his collaboration with Phillips. "We made him, we built him! Plus, he's a genius."

Indeed, these occasionally heated creative conversations existed only between Downey and Phillips, as Galifianakis told MTV — jokingly, we hope! — that he was never invited to participate in the collaboration process.

"These two differ. I wasn't allowed to talk," the comic actor said in his signature deadpan voice. "I would say something, and have you ever seen two people roll their eyes at the exact same time? That's what would happen."

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