Yes, Joker: Folie à Deux Is a Musical: Everything Joaquin Phoenix and Lady Gaga Have Said About Its Singing

Audiences excited for Joaquin Phoenix’s return as Arthur Fleck in the follow-up to Joker should go in knowing a very important detail: Joker: Folie à Deux is a movie musical. 

In case the trailers and casting of Lady Gaga as Harley Quinn didn’t make it abundantly clear, song and dance permeate writer-director Todd Phillips’ new sequel, with vocals delivered by Phoenix and Gaga themselves in often elaborately choreographed and designed numbers. 

Whereas the DC Comics-inspired Joker retold the origin story of a well-known Batman villain with gritty realism, Folie à Deux was inspired by Phoenix, Phillips and co-writer Scott Silver realizing that Arthur’s inner psyche could be expressed through song. “We just found ourselves writing more and more music into it,” Phillips told PEOPLE. “And I, at some point just thought, ‘I want to find an actor who brings music with them.’”

In addition to playing a version of Harley in the sequel, Gaga, 38, recently released a companion album called Harlequin, her recordings of songs used in the movie. Its tunes largely hail from the golden age of movie musicals, like “If My Friends Could See Me Now” from Sweet Charity, or old jazz standards like “I've Got the World on a String” and “Get Happy.” “That’s Life,” a tune made famous by Frank Sinatra that appeared in 2019’s Joker, resurfaces in Folie à Deux and then is sung anew by Gaga. 

“The question became, ‘how can we top ourselves?’” Phillips told Variety in August of developing the sequel after the initial Joker’s success. “And you can only do that if you do something dangerous.”

Of his musical numbers, he added, “Most of the music in the movie is really just dialogue… It’s just Arthur not having the words to say what he wants to say, so he sings them instead.” 

“We asked ourselves what would need to be true for two people to just break into song in the middle of a conversation?” Gaga told the outlet. “Where does the music come from when no one can hear it but the characters? Neither Arthur nor Lee are professional singers, and they shouldn’t sound like they are.” 

Phoenix, 49, echoed that sentiment in a cover story interview with Vogue published on Sept. 5. "I encouraged [Gaga] to sing poorly," he recalled. "I remember asking her to sing without her vibrato… 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 Vogue. By comparison, she added, "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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At a press conference for Folie à Deux’s world premiere at the Venice Film Festival on Sept. 4 (where its screening received an 11-minute standing ovation), Phoenix said that Gaga told him early in the filming process that they would sing vocals live rather than pre-record in a studio. “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."

The Oscar winner also said the actors “were working with a pianist on set, so each take was a different version of the song and of singing the song.” That unconventional way of shooting a movie musical, Phillips admitted to Variety, was a “nightmare” for him and editor Jeff Groth. 

But “particularly for Joaquin, so much of it is about feeling the moment as you do it,” Phillips said. “You can’t decide that in a sound studio three weeks before you show up to shoot it.”

At the Venice press conference, Gaga weighed in on the movie’s “very different” filmmaking techniques. “I wouldn’t necessarily say that this is actually a musical," she said. "The way that music is used is to give the characters a way to express what they need to say because the scene and just the dialogue is not enough.”

Joker: Folie à Deux is now in theaters.