In 2011, Kutcher costarred with Natalie Portman in No Strings Attached about a man and a woman who try to keep things strictly sexual before becoming romantically attached along the way. Later that same year, Kunis and costar Justin Timberlake's film Friends with Benefits — about two friends who begin a sexual relationship while trying to avoid becoming a couple — hit theaters.
On the latest episode of Kutcher's Peloton fitness series Our Future Selves, the actor, 44, jokes with guest Portman, 41, about making identical movies with his wife Kunis, 39, whom he wed in 2015 after three years together. Portman had costarred with Kunis in 2010's Black Swan.
"I think the first time we really started hanging out is when we shot No Strings together," Kutcher tells Portman as they work out together. "Which is weird because my wife ... was shooting basically the same movie, called Friends with Benefits."
"Yes," says Portman. "And Mila and I had just shot Black Swan together right before. So we were all making out with each other!"
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No Strings Attached was directed by the late Ivan Reitman and also starred Kevin Kline, Cary Elwes, Greta Gerwig, Mindy Kaling, Lake Bell and Ludacris. Friends with Benefits was directed by Easy A's Will Gluck and also starred Patricia Clarkson, Jenna Elfman, Woody Harrelson, Richard Jenkins — and Reitman's daughter Catherine Reitman also had a part.
Back in 2018, Portman (who met husband Benjamin Millepied on the Black Swan set) answered whether Kunis or Kutcher is the better onscreen kisser while on Watch What Happens Live! with Andy Cohen. "I've kissed them both, yeah," she said with a smile, revealing that Kunis is "obviously" the better kisser.
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On the WTF with Marc Maron podcast that same year, Kunis, who had costarred with Kutcher on the sitcom That 70's Show, talked about striking up a romantic relationship after their dueling twin movies.
"I did a movie called Friends With Benefits. He did a movie that was very similar called No Strings Attached. We lived our movies out. We were just like, 'Let's just hook up. Let's have fun. We're both single. We both trust each other. Everything's great,' " the Luckiest Girl Alive actress recalled at the time.
But then, "I was like, you know what, I actually care about you. I don't want to mess anything up so I'm just going to walk away before it becomes too much. And he was like, 'Got it.' And the next day, he showed up to my house and he was like, 'Move in with me' and I said, 'Okay.' "