Image copyright Getty Images Image caption Camila Cabello: "I was just kinda scared and overwhelmed when I was little."

Camila Cabello knows what she wants.

It's October 2017, and the singer is walking the red carpet at Radio 1's Teen Awards in London.

She stops to answer a few questions: What was it like working with Pharrell ("nerve-wracking"). Would you ever record a Spanish-language album ("definitely"). Then, as tradition dictates, we request a photo for the BBC's social media accounts.

Cabello blinks, then asks: "Do you mind if I take a selfie?"

Next thing you know, she's grabbed our phone and snapped four flawless portraits before being whisked away to her next interview.

It made an instant and lasting impression. Cabello had taken a throwaway moment and turned it to her advantage: The photo became our most-shared post from the awards, even after Gemma Collins fell through a trap door in the stage.

Image caption "Do you mind if I take a selfie?"

Fast forward to 2019, and Cabello is one of the biggest pop stars on the planet. She's sold five million copies of her debut album, Camila; opened this year's Grammy Awards with a Technicolor performance of her breakout hit Havana; and, alongside her boyfriend Shawn Mendes, released 2019's most-streamed single, Señorita.

Not bad for someone who, just seven years ago, was beset by crippling shyness.

"I was just kinda scared when I was little," says the 22-year-old. "I was super-shy. Easily overwhelmed. I didn't want people to look at me singing. I didn't want people to ask me to sing."

The story of her transformation is encapsulated in that Teen Awards moment. Cabello willed this version of herself into existence through hard work and self-belief, without surrendering her humanity.

"I see her as an absolute force of nature," says the star's manager, Roger Gold. "She worked on herself so much and so hard - as a singer, and a dancer and a songwriter. She knew she could make herself excellent in every category, and she knew what she had to do.

"That vision and that desire to get there... what it makes me think of is Madonna."

Across the border

Karla Camila Cabello comes from a family of strivers.

Born in Havana to a Cuban mother and Mexican father, she moved between the two countries until she was six, when her mother announced they were going on a trip to Disney World. Instead, they travelled from Cojímar to Mexico, where they caught a bus to an immigration centre on the US border.

After crossing into Texas, they made a 36-hour journey to Miami, arriving with just $300 and a backpack of possessions, including Cabello's Winnie the Pooh journal and her favourite doll.

For 18 months, they scraped by on the modest salary her mother, who'd been an architect in Cuba, made in the footwear concession of a department store.

Eventually, her father swam the Rio Grande to join his family, earning money by washing cars "in the blistering Miami heat", and saving up until the family had enough money to start a construction company.

Image copyright Alejandro Cabello Image caption The Cabello family (L-R): Alejandro, Sofia, Sinuhe and Camila

Looking back, Cabello says she was blissfully unaware of her parents' struggle.

"I don't think you realise that stuff as a kid," she says. "You're either happy or you're not.

"I remember being at my mom's job during the summer, under her desk playing house, and to me that was fun. When you're a kid all you really need is your imagination."

For a long time, her imagination was where Cabello lived. She'd rush home from school and devour the Disney Channel. "The Cheetah Girls, Hannah Montana, High School Musical: That was the golden era of my childhood, because all my friends were obsessed. We were just obsessed with it."

Online, she'd come up with silly nicknames to make her schoolmates laugh. "One year on Facebook, I was Billy Bob Billabong Cabello," she giggles. "I don't know why, I just thought that was funny."

When she hit her teens, her musical horizons widened to include Taylor Swift, Ed Sheeran and, especially, John Mayer's Free Fallin', which she played on repeat for an entire year.

"I would love to go on YouTube and sing karaoke and watch One Direction videos," she recalls. "I would just escape into music."

Image copyright Alejandro Cabello Image caption The singer spent hours devouring music as a child

Her own singing career got off to a rocky start, however. Auditioning for her fourth grade choir, the 10-year-old grew so nervous she forgot all the words to My Country, 'Tis of Thee.

At home, it was the same story. She'd belt out Beyonce's Listen in the basement but couldn't sing in front of her parents. When they asked, she'd burst into tears.

So it came as a surprise when, for her Quinceañera (15th birthday), she begged Sinuhe and Alejandro to drive her 12 hours from Miami to North Carolina to audition for the X Factor.

At the try-outs, Cabello was classed as "spare" - who'd only get to sing for Simon Cowell if someone else dropped out or filming ran ahead of schedule. Several times, she saw the opportunity being snatched away from her.

"I would be about to go on stage, with my mic in my hand, and they'd be like, 'No, sorry," she recalls. Eventually, a producer took pity on her, "because they were tired of seeing me disappointed".

On stage, in front of 8,000 people, she began the process of re-invention. She introduced herself as Camila, not Karla. And Camila wasn't shy or nervous. She was sweet, charming, a little bit goofy and an exceptionally gifted singer.

"I really didn't know if I could do it," she says of the audition. "I remember being the most nervous I've ever been in my life. And then I remember being on stage and being, 'Oh my God, I love this. There's such a thrill from this.'"

Image copyright Getty Images Image caption Fifth Harmony came fifth in the 2012 series of X Factor US: (L-R) Camila Cabello, Dinah Jane Hansen, Normani Kordei, Ally Brooke and Lauren Jauregui

Cowell drafted Cabello into a girl group, Fifth Harmony, cast from the same mould as One Direction. They scored some major hits - the spin-class anthem Work From Home has 2.2bn views on YouTube alone - before the dream came crashing down.

In December 2016, a day after playing New York's Jingle Bell Ball, the band released a statement saying, "we have been informed via her representatives that Camila has decided to leave Fifth Harmony".

Cabello hit back with a statement of her own saying, "I did not intend to end things with Fifth Harmony this way".

'Numb'

According to her account, Cabello left because her bandmates objected to her taking a larger creative role. The extra-curricular duets she'd recorded with Shawn Mendes and Machine Gun Kelly had also put noses out of joint. She'd been given the message that her solo plans were incompatible with the band.

The fall-out was brutal. At the MTV Awards, Fifth Harmony appeared with a Cabello look-a-like, who was violently yanked off-stage before their performance. When the band went on indefinite hiatus the following March, fans on social media told Cabello to kill herself.

Speaking to the BBC in 2017, Cabello said the break-up left her feeling "overwhelmed" and "numb"; but she resolved to move on.

She'd already started writing prototype songs. In hotel rooms on tour with Fifth Harmony, she'd look up Ed Sheeran instrumentals on YouTube and sing her own melodies over the top.

"I'd show them to people and say, 'Is there any way I can get this recorded by proper musicians?'" she says. "I didn't know it was an option for me to be a solo artist [because] I thought I was going to be in that group for 10 years."

One of the people who heard the demos was Fifth Harmony's lawyer, Roger Gold. who was instantly impressed.

"I remember thinking to myself, 'Is she really as good as I think she is?'" he says. "I couldn't believe how fresh it sounded."

Image copyright Dennis Leupold Image caption Cabello says she wanted her new album "to sound like what falling in love feels like".

Seizing the opportunity, Gold offered to be Cabello's manager, and started hooking her up with professional songwriters.

But while her collaborators were pop A-listers like Sia and Charli XCX, the singer's first few solo singles - Crying In The Club and OMG - were neither distinctive nor exciting. Luckily, Cabello had a song in her back pocket that would change all that.

Called Havana, it drew on the singer's Cuban roots, fusing a rumba piano motif to the heavy 808 beats of Atlanta hip-hop, carving out a unique sound that defined her debut album.

The song had a long and public gestation; revised and re-recorded several times while Cabello toured the US in support of Bruno Mars.

A forensic investigation of the song's evolution on Reddit showed how lyrics were tweaked and melodies substituted from one performance to the next, as Cabello determinedly whittled away at the song's structure for four months.

"We started off with the chorus and I was like, 'This chorus is sooo good,'" she recalls. "But we must have written at least 10 different versions of a verse and a pre-chorus and every time I was like, 'This is not good, this is not good.' Almost to the point where everybody on my team had started to give up on the song because we just couldn't finish it.

"It was a long process of, week after week, trying to figure it out until the moment where I finally thought, 'this is right.'"

Image copyright Epic / Syco Image caption Havana topped the charts on both sides of the Atlantic

Her instincts paid off. In its final incarnation, Havana became the most-streamed song by a female artist of all time; racking up 1.3bn plays on Spotify alone. It marked a turning point in Cabello's career.

"In the beginning I felt like a deer being born," she says. "You know, like when they can't walk? I was just stumbling, trying to find my way. I didn't have the confidence to say no. After Havana, I never did anything again that I didn't feel 100% passionate about."

She grasped the opportunity with both hands. Havana was rewarded with a big-budget video, riffing hilariously on Spanish soap operas; and Cabello, who severely doubted her abilities as a dancer, threw herself into rehearsals for the song's steamy dance breakdown.

"That was a really big risk for her. She had never done anything that intense up to that point," says Calvit Hodge who, along with Sara Bivens, has choreographed all of Cabello's videos and live shows.

"The first day of rehearsal was mostly watching body postures and her movement; and we incorporated a lot of that. And then we pushed her."

'We all cried'

Three gruelling days later, the routine was perfected - and the professionals were in awe.

"She's such a hard worker that anything's attainable," says Bivens. "Dance doesn't really come easily to anybody, especially of this calibre, but she superseded our expectations."

The attention to detail never wavered. Together, Cabello, Bivens and Hodge put together more than 20 live performances of Havana, each with individual choreography and staging, culminating with a Grammys extravaganza that seemingly crammed the whole of West Side Story into a four-minute performance.

"After that performance, we all literally cried - and I'm not much of a crier," laughs Hodge. "The biggest compliment we received was from people of the Latin community, who felt they'd been represented properly.

"We always try to make sure Camila's heritage is present in her performances, because that's a very strong part of who she is. And her grandma was really happy with it, so that was really important too, because she's from Cuba."

As soon as the Grammys wrapped up, however, Cabello stepped away from the limelight to concentrate on her second album.

"She said, 'I'm not going to come out of the studio until I've beaten my last album,'" recalls her manager, Roger Gold.

In total, it took eight months, covering a period where "other artists were putting out back-to-back albums, only a few months apart," he says.

"So it was hard for us, and for her, to ignore the noise and go into the studio and take the time she needed."

But Cabello is cut from a different cloth. In some respects, she's the last of a dying breed - a glowing, aspirational star in the lineage of Janet Jackson or Jennifer Lopez, eschewing the edgy street smarts of Billie Eilish or Ariana Grande.

"I feel like everybody is so cool right now," she observes, "and I guess I can be cool sometimes - but for the most part, cool isn't the word I would use to describe my personality... at all."

So it's fitting that her new album is themed around the least cool, but most important, emotion of them all: Falling stupidly, helplessly, head over heels in love.

"Falling in love is the ultimate inspiration, because it draws the most emotion out of you," she says. "I don't think there's anything else like it, getting carried away by your emotions."

Titled Romance - what else? - the album explores love from all sides. Over the island vibes of Liar, Cabello succumbs to temptation ("boy, what if you kiss me? / And what if I like it?"); while the experimental vocal harmonies of Bad Kind Of Butterflies have her confessing to an affair of the heart.

Making the record, she leaned into improvisation - freestyling melodies in the studio instead of turning up with meticulously-prepared notes and song concepts. As a self-confessed perfectionist, she found she had to force herself to let go.

"I still have that instinct," she says. "Sometimes I don't even want to move because it's not perfect or because I'm scared - but I don't let it rule me any more."

Allowing herself to be spontaneous gave Romance an intimacy her debut sometimes lacked.

Easy is an obvious highlight - with Cabello radiant after finding a boyfriend who loves her, flaws and all, from the "crooked teeth" she "never really liked" to the "stretch marks all around my thighs".

The man in question is clearly Canadian singer Shawn Mendes, a friend who became more than a friend after they hooked up to record Senorita earlier this year, but Cabello is reticent when it comes to discussing their relationship.

"I'm tight-lipped about it because I want to protect it," the 22-year-old recently told Elle magazine - but she does say that falling for a friend "is a different kind of feeling".

"This person feels like home to you because you've known them for such a long time," she smiles.

Image copyright Reuters Image caption Cabello is dating Shawn Mendes, whom she collaborated with for Senorita

But perhaps the most moving song on the record is the closing track, First Man. Addressed to her father, it pin-points the wrenching moment a dad has to let go of his little girl.

"You're on the driveway faking a smile / You wish you could tell him he doesn't deserve me," she sings over a delicate piano. "So I had to start the car and turn around / To tell you, you were the first man that really loved me."

It's a powerful moment that confirms her growing confidence as a songwriter and vocalist.

"She writes some of the best melodies in pop music right now," says Justin Tranter, who worked on Cabello's album after crafting hits for the likes of Justin Bieber, Britney Spears and Ariana Grande.

"And also what she stands for and what she represents is incredibly important. Being a Cuban-American owning the charts while Trump is in the White House is very, very impactful."

Image copyright Epic / Syco Image caption The star is set to tour the UK next year, after filming the title role in a live-action adaptation of Cinderella

The politics aren't just symbolic. At the 2018 Grammys, Cabello gave a speech in support of the Dreamers - children of undocumented immigrants fighting to stay in the US - and has written passionately about her experiences as an immigrant.

Her principles and her tenacity all originate at home, says Gold.

"Her parents have been a huge influence on her and are miraculous people themselves," he says. "They share a scrappiness and a point of view about the world - that there's challenges, but you know what you want, and you don't let anything stand in your way."

Cabello puts it differently.

"Every day I'm trying to think, 'What's the most authentic I can be?' That way, I can't really go wrong, because I'm just being myself.

"And if people think that's not cool enough, or not serious enough, it's like, 'Well, we wouldn't be friends in real life anyway. Who cares?'"

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