Lady Gaga and Joaquin Phoenix on Singing Live in Camera for ‘Joker: Folie à Deux’: ‘It Was Really the Only Way’

“ Joker: Folie à Deux ,” the sequel to the 2019 Oscar-winning box office smash that presented a villain origin story for Arthur Fleck ( Joaquin Phoenix ), finds the failed comedian in Arkham State Hospital, on death row for the crimes he committed in the first film.

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It’s there he meets volunteer music therapist Harleen Quinzel (Lady Gaga), with a dark backstory of her own. The two form a dangerous obsession (hence the title) as Arthur stands trial in courtroom scenes broken up by fantastical jukebox musical numbers that cover everything from the Bee Gees to Billy Joel. “It was all meant to feel like music Arthur may have listened to with his mom when he was younger,” director Todd Phillips , who co-wrote the script with Scott Silver, said at the film’s Venice press conference.

Phillips joined his two stars on the Lido Wednesday afternoon for a press Q&A ahead of the world premiere at the Sala Grande. The legacy of the first “Joker” film’s Venice bow — where it stormed the Lido and ended up winning the Golden Lion — isn’t lost on the director, who said he is more nervous this time around because of that precedent.

“It feels right, it feels correct to be back in Venice. It felt like the [right] launching-off point for us for this second film,” Phillips said. “We have a very strong feeling towards Venice and what happened last time, not just winning the festival but the way the film was treated… I am a little more nervous, and I think it’s a lot easier to come into something as the insurgent as opposed to coming in as the incumbent, so there are a lot more expectations on a second film. There’s a sense of more nervousness than I had with the first one.”

As Phoenix and Gaga explained, most of their singing happened live in camera, and you can tell from the way singer Gaga’s voice is less polished than in a proper musical like “A Star Is Born.” “I had this dream I was performing as Joker doing songs and I just called Todd because I thought there might be something there, and there wasn’t,” a deadpan Phoenix said.

“Part of the joy for me was taking these songs that were standards and trying to find a way that it felt like they were specific to the characters, that it was the only way the characters could express themselves, with these songs sung in this way… Originally, we started with some references. I had Frank Sinatra, Sammy Davis Jr., and these legends, and I think we started trying to emulate that sound, or at least I did before I realized, wait a second, this is not who Arthur is, who Joker wants to be,” Phoenix said.

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“Stefani [Germanotta, aka Lady Gaga] early on was like, ‘We’re going to sing live,’ and I was like, ‘No, we’re not, you can sing live if you want,’ and ultimately we did it, and it was really the only way,” Phoenix said. “Not only did we sing live, 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.”

“The way we approach music in this film was very special and extremely nuanced,” Gaga said. “I wouldn’t necessarily say that this is actually a musical. In a lot of ways, it’s very different. 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. Like Joaquin said, we did a lot of this live, and the pianist on set with us was sort of like an actor off-camera in the scene with us. We worked really hard also on the way we sang. For me, it was a lot about unlearning technique and forgetting how to breathe and allowing the song to completely come out of the character.”

Phillips added, “If you remember the first film, Arthur has a musicality to him. He is often dancing to express the way he feels. Hildur Guðnadóttir’s score is almost a character in the first film. So when [the sequel] started taking shape with actual music elements, we thought, what if we got Lady Gaga who actually brings music with her?”

As for how much weight Phoenix lost for the role — Arthur Fleck is even more gaunt and shriveled here, his scapula caving inward — the actor said, “I’m not going to talk through specifics of the diet. This time, it felt a bit more complicated just because there was so much dance rehearsal that we were doing, which I didn’t have last time. I’m now 49. I probably shouldn’t do this again. This is probably it for me.”

“Joker: Folie à Deux” premieres in U.S. theaters from Warner Bros. on October 4.