EXCLUSIVE: Robert Downey Jr. Reveals Which 'Civil War' Co-Star is His Wife's 'Free Pass'

Hint: It's probably not the one you're thinking of (because you were thinking of Chris Evans and it's not Chris Evans).

On Wednesday, Robert Downey Jr. joked in an interview with Howard Stern that his Iron Man love interest, Gwyneth Paltrow, is his "free pass" -- as in, the one woman his wife, Susan, would be okay with him sleeping with.

Later that day, Downey spoke to ET at a New York City screening of Captain America: Civil War where he got the chance to turn the tables, so to speak, and reveal which of his co-stars he'd choose to be his wife's "free pass."

"I'm gonna go [Paul] Bettany, you know?" admitted Downey Jr., referring to the actor who voiced Iron Man's computer side-kick Jarvis and now stars as The Vision in Marvel's superhero saga. "He's got that European, British flair."

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Downey, Jr. wasn't joined by his wife on the red carpet for the New York screening, which is the latest in a string of cities the 51-year-old star has traveled to while gearing up for the release of the upcoming action epic. Which begs the question: Which stop on the Civil War promotional tour was the actor’s favorite?

"I'm from New York, so I gotta say New York, but I mean, Berlin was amazing, Paris was a blast, London is always fun," Downey, Jr. recounted. "I got to swing through San Francisco on the way home for a minute. I love the planet. I'm glad to be on the planet."

And the planet is happy about the forthcoming Marvel film. This installment in the Captain America series has already enjoyed massive, record-breaking pre-sales, which Downey, Jr. says is due to it being "a really good movie."

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"I think it deserves it and fans are loving it and I think people are gonna enjoy it," he shared.

Captain America: Civil War explodes into theaters May 6

For more on the Iron Man star's candid, sit-down interview with Howard Stern, check out the video below.