Lady GaGa stayed in her 'A Star Is Born' character for years.

The 35-year-old star featured in the 2018 movie as Ally Maine and admitted that she kept up the persona for much longer than her 'House of Gucci' alter ego Patrizia Reggiani - who spent months living every waking moment as.

Speaking during a Variety Actors on Actors conversation with Jake Gyllenhaal, Gaga said: "I would actually say playing a character for me is like living one long song, one long song that lasts for months. For 'A Star Is Born', it was years for me."

The 'Bad Romance' hitmaker revealed that she was keen to shed her 'House of Gucci' persona as Patrizia is a convicted killer.

Gaga explained: "I dropped her faster because she was a killer and there were some things about the transformation for me psychologically that were super challenging.

"When I watch the movie, it looks like I'm watching a montage of my life. I don't feel like I'm watching a film."

The star also revealed that she was immediately drawn to Patrizia after being approached to feature in Ridley Scott's film, which tells the story of how Patrizia masterminded the murder of her former husband Maurizio Gucci (Adam Driver).

Gaga said: "The first thing I thought when I read the script was 'OK, they want some woman to use her body and her manipulation to get money from this incredibly wealthy man.'

"And the more that I dug through it, I realised that she was really in love with him. And women are complex creatures, and we're complicated, and it's never one single story. It's many stories."

She continued: "I wanted to inject a reality into her that was multifaceted and broken. When I think about her as a character, I think of me taking little bits of glass from tons of different women and encapsulating them into one character that I still believe to be truly her, but I think insanity is subjective."