Lady Gaga drew on 'mania and chaos inside' to play Harley Quinn

Lady Gaga used her experience with "mania and chaos inside" to inform her performance of Harley Quinn.

The 38-year-olod actress portrays the comic book character in 'Joker: Folie à Deux' and she's explained how she drew on her personal way of handling feelings of being overwhelmed to develop a "quietness" for her alter ego.

She told the new issue of America's Vogue magazine: "Harley Quinn is a character 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.

"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?

“I would say that I worked from a sense-memory perspective: 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?”

Music features prominently in the film but Gaga's pop star background wasn't helpful as she needed to "undo" her techniques in order to sound like a regular person.

She said: "I worked really hard on that, kind of trying to undo all my technique. 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.”

Her co-star, Joaquin Phoenix, added: "[Gaga] encouraged me to sing live and I encouraged her to sing poorly.

"I remember asking her to sing without her vibrato. She has a beautiful vibrato—too beautiful. I think she felt naked without it.

"But as soon as she moved away from technique she unlocked her character’s voice.”