The Grammy-nominated artist admits she had "never really properly done a musical" before.
"When I read it and understood it I was like, 'How on earth are they going to make this movie?
"But we never doubted him ever."
The Grammy-nominated artist admits she had "never really properly done a musical" before.
"When I read it and understood it I was like, 'How on earth are they going to make this movie?
"But we never doubted him ever."
In the film, which also stars Zoe Saldaña, Karla Sofía Gascón and Adriana Paz, Selena plays the wife of the Cartel leader who becomes Emilia Pérez, played by Karla.
"Jessi is the wife, she’s a mother, she’s struggling with confusion - losing the love of her life and all the confusing parts of it," Selena tells Radio 1 Breakfast Show's Greg James.
"You’d think it’s a crime thriller," says Zoe, who stars as Rita - a lawyer tasked with arranging Emilia's gender reassignment surgery.
"But in reality, it’s a journey of four women trying to find their authentic selves and their versions of freedom and love."
Zoe says before her transition, Emilia is an "unredeemable character" but audiences have a "yearning for her redemption".
Emilia Pérez is set to be released in cinemas and on Netflix in the UK later this month but has already had generally positive reviews.
Selena, Zoe, Karla and Adriana have already bagged the prize for best actress at Cannes Film Festival and Variety suggests the film could be the streaming platform's first to win best picture at the Oscars.
However, Slant says the film "tries to be a lot of things, only to end up being about very little" and it's also been accused of using "tropes of trans stories" by Empire.
Karla, who is a trans actress, told Deadline that she felt "a lot of responsibility... for this movement around me".
"I’ve done a lot of trying to educate people, to make them respect me."
Selena was personally praised as a "welcome surprise" by Entertainment Weekly, which said she has "shed any remaining hints of her Disney Channel origins".
The 32-year-old's breakthrough role came on Disney Channel's Wizards of Waverly Place in 2007 but she has continued acting and was recently nominated for awards for her role in Only Murders In The Building.
"I knew I had to embody this other person," Selena says about playing the role of Jessi.
"It all had to come from her. I couldn’t be the pop star - as cheesy as that sounds."
Despite her success in both acting and music, Selena says she still felt the nerves.
"Because I was so honoured and I knew Jacques [Audiard] was such a visionary and I just wanted to be a part of it."
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