Ariana Grande has told the BBC that she channelled her personal feelings of loss when filming Wicked.

"Losing someone you love is something we've all unfortunately had to experience - and sometimes we have the privilege to say goodbye and sometimes we don't," she says.

Grande, 31, plays Galinda Upland in the film, which is an adaptation of the hugely successful stage musical exploring the Wizard of Oz universe from the perspective of two witches.

The two-time Grammy award winner has suffered personal tragedy in recent years, after the 2017 Manchester bombing of her concert and the death of her former partner Mac Miller a year later.

She says appearing in Wicked, one of the first Broadway shows she saw as a child, "feels like a homecoming".

"This music has always brought such comfort and now being able to spend time with it and be trusted with it is the privilege of a lifetime."

In the weeks running up to the film's release, the close relationship between Grande and co-star Cynthia Erivo has been in the spotlight.

"From the moment we were cast, Cynthia invited me over and we hung out for five hours and we laughed and we cried and got to know each other.

"We had a real conversation right off the bat about creating a safe space for each other and being honest with each other," she says.

Grande and Erivo's characters begin in the Oz universe as university students, before later becoming enemies as Glinda the Good Witch and Elphaba the Wicked Witch of the West.

Erivo, 37, has described her role as "a real honour" and nods to the foundations formed by the original stage actors Kristin Chenoweth and Idina Menzel, who she calls "the architects".

"We've been handed something really special and it's a dream come true and truly big shoes to fill," she adds.

Critics have so far given the film mixed reviews. The Guardian's Peter Bradshaw praised the "sugar-rush fantasy" and awarded four stars, describing Wicked as a "blast of entertainment power".

There was another four-star review from Empire's Helen O'Hara, who said director Jon M Chu "uses every bell and whistle possible to turn the stage show into a movie epic".

However, in a two-star review, the Telegraph's Robbie Collin described Wicked as "utterly exhausting and hopelessly miscast", adding that there was "no conceivable artistic argument" to have split the the Broadway show into two films.

The Independent's Clarisse Loughrey awarded three stars and questioned the way it was shot, with characters often "aggressively backlit".

"Jon M Chu treats his Oz as if it were as mundane as a city block," she added.

But Screen Daily's Fionnuala Halligan concluded: "It’s so doggedly faithful to the show, so emphatically orchestrated and so powered by Cynthia Erivo's exceptional performance, that resistance to its 169 minutes of theme park magic becomes futile."

Erivo, who received a best actress nomination at the Oscars for her portrayal of Harriet Tubman in the biopic Harriet in 2019, is also a decorated stage performer who received a Tony Award in 2016 for the Broadway adaptation of The Color Purple.

She says she was able to draw on her own experiences of struggling with acceptance for the role of Elphaba, who is outcast for her green exterior.

"Whether you feel 'other', or you feel different from everyone else, I think both of us have experience in those spaces that we have used to infuse our characters," she says.

Wicked, which first came to Broadway in 2003, has gone on to be the third-highest grossing theatre show in the world, behind The Lion King and The Phantom of the Opera.

Many have pinned its enduring success with audiences on the relatability of its content - from Elphaba's struggle with self-identity to Glinda's difficulty in making moral choices.

Its reimagining for the big screen also stars Oscar winner Michelle Yeoh as Madame Morrible and Game of Thrones' Peter Dinklage as the voice of Doctor Dillamond - who is an animated goat.

Oscar nominee Jeff Goldblum appears as the Wizard of Oz and British star Jonathan Bailey - who has received international recognition in recent years after starring in Netflix hit Bridgerton - as Fiyero.

Goldblum says the central themes of the film, which include embracing diversity, were important to the cast, who were able to "come together to work and appreciate each other with empathy, compassion and love".

Bailey also says everyone he worked with had their own "Elphaba story", adding "we have at points in our lives felt different".

He says: "In this film particularly, it's the superpower of individuality which becomes a power to harness.

"I think it's really important right now as well, this theme that there's more that unites us than divides us."

The musical has been a West End and Broadway institution for more than 20 years, but Chu says the central themes of the plot are more relevant than ever.

"Elphaba says something has changed within me, something's not the same - and that's the line that really got me into this movie, I felt like we all feel uneasy," he says.

Chu, who also directed Crazy Rich Asians in 2018, says he received the script for the film during the pandemic, which made him think about how the film could reflect his real-life experience of looking for truth in a confusing time.

He says the cast also made themselves "emotionally available" during filming and were able to put themselves personally in the shoes of their characters.

"Ariana, Cynthia and Jeff were talking about the real-world stakes of what we were putting into these characters," he adds.

"It wasn't just about global politics, it was more personal than that.

"We were all going through stuff in our own lives and I think they were generous to offer that up within the roles of Glinda, Elphaba and the Wizard."