Lady Gaga Had to Unlearn Her 'Trained' Singing Abilities to Play Harley Quinn: 'There's Plenty of Bum Notes'

Harley Quinn isn't as great of a singer as Lady Gaga.

In a new interview with Empire, the Grammy and Oscar winner opened up about the process of unlearning her "trained" singing abilities while playing Harley, a.k.a. Lee, in the upcoming Joker: Folie À Deux film.

"People know me by my stage name, Lady Gaga, right? That’s me as that performer, but that is not what this movie is," the 38-year-old musician and actress, whose real name is Stefani Germanotta, told the outlet.

"I’m playing a character," added Gaga of the upcoming film, out Friday, Oct. 4, which also stars Joaquin Phoenix in its titular role. "So I worked a lot on the way that I sang to come from Lee, and to not come from me as a performer."

The "Bad Romance" singer has been performing live for over a decade and acted in films like House of Gucci and A Star Is Born, the latter of which saw her combine her vocal and acting talents. But Joker: Folie À Deux has been a different experience.

"How do you take music and have it just be an extension of the dialogue, as opposed to breaking into song for no conceivable reason?" said Gaga. "It was unlike anything I’ve ever done before."

Part of her preparation for the role included learning how not to sing as well as as she usually does. "It was unlike anything I’ve ever done before," she said. "I’m a trained singer, right? So even my breathing was different when I sang as Lee."

Gaga continued, "When I breathe to sing on stage, I have this very controlled way to make sure that I’m on pitch and it’s sustained at the right rhythm and amount of time, but Lee would never know how to do any of that. So it’s like removing the technicality of the whole thing, removing my perceived art-form from it all and completely being inside of who she is."

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Directed by Todd Phillips, Joker: Folie À Deux serves as a sequel to 2019's Joker, for which Phoenix earned an Academy Award for Best Actor. The upcoming film's latest trailer was released on Tuesday, July 23.

In a May interview with Access Hollywood, Gaga said of the film, "I loved working with Joaquin, I loved working with Todd. I've never done anything like I've done in this movie before, so it's all going to be completely brand new and really fun."