Joaquin Phoenix 'Encouraged' Lady Gaga to 'Sing Poorly' in Joker 2: 'She Felt Naked Without' Her Vibrato

Lady Gaga had a unique challenge in Joker: Folie à Deux.

The singer-actress, 38, has a voice and musical talent that has earned her 13 Grammy Awards, among other accolades. But to play Harley Quinn in the upcoming Joker sequel, she had to go a different direction, said costar Joaquin Phoenix.

"I encouraged her to sing poorly," Phoenix, 49, told Vogue in a cover profile of Gaga for the magazine's October 2024 issue. "I remember asking her to sing without her vibrato."

"She has a beautiful vibrato — too beautiful. I think she felt naked without it," he added. "But as soon as she moved away from technique she unlocked her character’s voice.”

"I worked really hard on that, kind of trying to undo all my technique," Gaga told the magazine. "I mean, Ally Maine in A Star Is Born is a singer and it’s a movie about people who make music. That is not what this film is about at all.”

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Aside from musical challenges, Gaga told Vogue she "had a different experience" with her character than the Harley "people know from the ether of pop culture."

"I had a different experience creating her, namely my experience with mania and chaos inside — for me, it creates a quietness," Gaga explained. "Sometimes women are labeled as these overly emotional creatures and when we are overwhelmed we are erratic or unhinged."

"But I wonder if when things become so broken from reality, when we get pushed too far in life, what if it makes you … quiet?" she added.

The Born This Way artist went on to say she "worked from a sense-memory perspective" on the film — in essence, "What does it feel like to walk through the world and be … braced, in an intense way. And what happens when you cover up all of the complexities beneath the surface?”

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From director Todd Phillips, Joker: Folie à Deux recently had its world premiere at the Venice Film Festival on Sept. 4, where it received an 11-minute standing ovation.

During a press conference earlier that day, Phoenix said Gaga "was like, 'We’re gonna sing live,’ and I was like, 'No, we’re not — you can sing live, if you'd like.' And ultimately we did it, and it was really the only way."

And "Not only did we sing live," the Oscar winner continued, "but every part of the recording was live."

"We didn’t sing to completed tracks or a click track. We were working with a pianist on set, so each take was a different version of the song and of singing the song, so that felt really exciting and created an energy that was necessary," Phoenix said.

Joker: Folie à Deux is in theaters Oct. 4.