Tate McRae had one of the biggest break-out hits of last year with You Broke Me First - but she never intended to become a pop star.

From the age of six, she had trained as a dancer, attending Canada's prestigious Alberta Ballet for 11 hours a day, filling her free time with competitions and galas.

She was so dedicated that she took lessons in rhythmic gymnastics with "super-intense Russian coaches" to improve her flexibility. It quickly paid off.

At the age of 11, she was awarded a two-week scholarship at the Berlin State Ballet after winning the silver medal at the 2015 Youth America Grand Prix - the world's largest student ballet competition.

The following year she successfully auditioned for the US TV series So You Think You Can Dance, performing a stunning backwards walkover that prompted judge Paula Abdul to declare: "You are a gift from God."

On the night her episode was broadcast, she watched the footage backstage at a Justin Bieber concert, where she'd been selected as a backing dancer for a one-off show in Canada.

This, she assumed, would be her life.

"I was kind of clueless," says McRae. "I either wanted to be a backup dancer, or part of a contemporary dance company in Europe, but I was trying to keep my options open."

Her musical career came about by chance. After So You Think You Can Dance, she'd set up a YouTube channel called Create With Tate to showcase her choreography. But in its fourth week, her camera failed and all her dance footage was lost. Determined not to skip a post, she decided to upload a song instead.

"Once I commit to something, I'm really gonna make sure it happens," she says. "So I went into my room for 20 minutes, shut the door, wrote a song, came out, played it on a piano and posted it. I didn't even know where it came from. It was an accident."

That accident, a piano ballad called One Day, was subsequently viewed 36 million times.

In the video, McRae picks out the chords on a keyboard marked up with green stickers to show where her fingers should go - but the naivety of her technique is offset by the intimacy and emotion of her vocals.

Her lyrics, too, are strikingly perceptive for a 14-year-old, painting a splendid vignette of unrequited love: "It's impossible to get you off my mind/I think about a hundred thoughts/And you are 99."

As the views racked up, she decided to keep writing, even though she'd never studied music. To this day, she still starts songs by looking up chords on the music education website Chordify.

"I didn't really realise how hard songwriting was because I would just get home from dance at 10 and write a song in half an hour," she says.

"I just thought of it as this outlet at the end of the week, where I would let out all the feelings that I'd been keeping inside of me."

By 2019, McRae had been offered deals by 11 record labels, eventually signing with RCA because they supported her maintaining a dance career in parallel with her music.

To her immense surprise, the label then presented her with a song written by Billie Eilish and her brother Finneas. Called Tear Myself Apart, it would become her first official single.

"I still don't really know what happened, but they were like, 'Here, it's for you,'" she recalls.

"It was really exciting because I was a big, big fan of Billie - and then I got to meet her at one of her shows. She was amazing, just super-sweet."

But it was one of McRae's own songs - You Broke Me First - that became her breakthrough hit. A moody, minimal pop song, it once again showcased her ability to pinpoint a universal emotional truth.

"I know you, you're like this," she sings to an ex who's come crawling back after six months. "When things don't go your way, you needed me to fix it."

Powered by McRae's bruised vocals, it became a top 10 hit in the UK, and was streamed more than a billion times last year.

Success came at a strange time. The song was the last track McRae recorded before the pandemic, and she ended up filming the video using an iPhone taped to a tissue box on the bonnet of her mum's car.

"Sometimes I think the simpler, the better," she says of the low-budget approach. "Honestly, if it's in your performance, in your face, it can convey a lot."

But confoundingly for someone whose music is obsessed with melancholy, McRae says she's never fallen in love and never had her heart broken.

Instead, she considers herself an emotional sponge, who absorbs other people's feelings and "blows them up into stories".

"When I write songs, I'll really, truly feel them, even if they haven't happened," she says.

"And in the [recording] session, I will put myself completely in those situations. I'll feel every single emotion that I would have felt if I was in that relationship - which is a very odd feeling."

Such intense levels of empathy must have made the process of recording McRae's new EP exhausting.

All six of the songs deal with doomed relationships, from Slower, written about a crush she had at the age of 13, to the I-can't-quit-you pop anthem Rubberband, with its killer chorus: "I've got this rubber band/on my wrist/and I snap it every time/that I think about your lips."

With deliberate irony, McRae called the EP Too Young To Be Sad.

"I just wanted the title to contradict it all," the singer laughs. "We can't just dwell on heartbreak and drama, we need to live our lives. So the title kind of disregards the whole thing but also wraps it up perfectly."

With Slower already added to Radio 1's playlist, the EP looks set to cement McRae's position as one of pop's brightest new stars. To her fans - aka the Tater Tots - it's a bittersweet moment.

"Are you guys also kinda sad that Tate isn't our little secret anymore?" wrote one under the video for You Broke Me First last year.

"It's the cutest comment, because they've been with me since day one," says the singer.

"I was really terrified when I started working with producers and co-writers because I was like: 'They're not gonna like it.' And it's been incredible to see them join me and see me be like: 'Alright guys, I'm now going on my first award show and I'm taking you with me.' It's really cool I love it."

Now aged 17, McRae is one of the first generation of pop stars who've grown up completely online. From her beginnings as a dancer, to a reality TV contestant, vlogger, singer and now pop star, huge swathes of her life have been documented in video.

Last January, she even put together her own highlights reel, looking back at 10 years in the spotlight.

"I love editing those," she says. "I don't like to sit back and be proud of what I do because I'm always working for the next thing - but it's so cool to reflect on the past and go: 'Wow, that's how much you've done and that's the kind of person you've become.'"

Although she got her big break on YouTube, McRae was built for Tik Tok because (a) dancing and (b) emotional ballads. It's no surprise that she's amassed 2.2 million followers since joining the app in November 2011.

"It's literally the main source of what teenagers are thinking about every single day," she says.

"It feels like a huge group chat where everyone comes together and sees the same things, and thinks the same way. So it's important to be on it and, obviously, make your songs go on there."

Even so, she realises the devil's bargain of social media - that it allows her to connect with fans and promote her work, while robbing her of her privacy.

"Sometimes I actually forget that I'm a public figure and that everyone watching can form their own opinions on me without actually meeting me. It's the craziest feeling," she says.

Recently, she says, she's started shutting off her social accounts "as much as I can, to maintain my own life". Instead, she wants to communicate through her lyrics.

"I like to be as vulnerable as I can in my music so that fans can really get to know what's inside my brain," she says.

"I've been writing all pandemic and I just want to put everything out."

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