During an appearance on Dax Shepard's "Armchair Expert" podcast, the 37-year-old actress talked about how she had to record herself having a fake orgasm for the movie.
Johansson played Samantha, an AI system that operated a phone belonging to Phoenix's character. "Her" featured a scene where the two engage in a form of phone sex which required an audio recording of Johansson fake orgasming.
"We tried to get through one take, and he was like losing it," she said. "He left the studio. He needed a break."
The "Black Widow" star explained, "You don't want to hear your voice ever. You definitely don’t want to hear what you sound like having an orgasm. You definitely don’t want to hear what you sound like having a fake orgasm — ew. It’s so gross. It was so bizarre."
The "bizarre" requirements of the film appeared to have later paid off when director Spike Jonze won an Oscar for original screenplay at the time of its release and the film was nominated for best picture.
Elsewhere on the podcast, Johansson opened up about the effects of being hypersexualized by the media and Hollywood early in her career.
"I kind of became objectified and pigeonholed in this way where I felt like I wasn't getting offers for work for things that I wanted to do," she explained. "I remember thinking to myself, 'I think people think I'm 40 years old.' It somehow stopped being something that was desirable and something that I was fighting against."
"I think everybody thought I was older and that I'd been [acting] for a long time, I got kind of pigeonholed into this weird hypersexualized thing," Johansson continued. "I felt like [my career] was over. It was like: that's the kind of career you have, these are the roles you've played. And I was like, 'This is it?'"
Back in April, the actress touched on an example of this hypersexualiztion by addressing a wild rumor that she and Benicio Del Toro hooked up in an elevator at the Chateau Marmont in 2004.
While appearing on an episode of theSkimm's 9 to 5ish podcast, Johannson addressed the talk, calling it "outrageous" and "absurd."
"There was a rumor that went around for a very long time that said that I had sex in an elevator," she recalled. "That was a story that followed me for a long time. But I always thought that was outrageous."
"I was always thinking to myself, 'That would be tough. It's a very short period, the logistics of that seem so unappealing to me,'" she added. "I'm a person who's terrified of being caught doing something I'm not supposed to be doing. So that made the story even that much more absurd to me."