Lorde says David Bowie inspired her album, as she releases her new single, Green Light

After a week of elaborate teases, pop star Lorde has finally unveiled her long-awaited new single, Green Light.

Inspired by a heartbreak, it juxtaposes downbeat lyrics with a euphoric chorus, over a driving percussion loop.

The song received its first play on BBC Radio 1, where Mistajam made it his hottest record in the world.

It's Lorde's first new material since the Disclosure collaboration Magnets in 2015 and precedes her second album, which is due later this year.

"Finally! It's only been three years, huh?" she told Radio 1.

Here's all you need to know about the song - and Lorde's new album.

Lorde paid tribute to David Bowie at last year's Brits, backed by many of the star's former band

The album was inspired by David Bowie

David Bowie believed the Lorde was "the future of music" - which is why the singer was chosen to pay tribute to him at last year's Brit Awards.

Going back to the studio after that performance, she said his spirit informed her writing.

"I feel like the whole time spent writing this record, I've had him in my thoughts, I've had him in my heart," she told Mistajam.

"It's hard not to make something and not think, 'What would David think of this? If I could play it to him, what would he say?'"

Fittingly, portions of Lorde's album were recorded in New York's Electric Lady studios, where Bowie wrote Fame and recorded his swansong, Blackstar.

Green Light is the start of a "new chapter"

"I am so proud of this song," wrote Lorde on Twitter. "It's very different, and kinda unexpected. It's complex and funny and sad and joyous and it'll make you DANCE."

"It's the first chapter of a story I'm gonna tell you. The story of the last two wild, fluorescent years of my life.

"This is where we begin."

It's about rebuilding yourself after a devastating break-up

Lorde's debut album, Pure Heroine, was released in 2013

Lorde told Mistajam that Green Light was "about me trying to figure out how to put myself back together" after her first significant heartbreak.

It opens on a sombre note, as Lorde recalls the beginning (or end?) of her relationship.

"I do my makeup in somebody else's car," she sings over a minor key piano. "We ordered different drinks at the same bar."

"Did it frighten you, how we kissed when we danced on the light-up floor?"

But Lorde goes on to call her lover a "liar", practically spitting the line: "Those rumours they have big teeth, they bite you."

As she ramps up towards the hook, she's getting ready to pack her belongings - while admitting she's finding it hard to finally make the break.

"I wish... I could just let go," she sings as, in the background, a chorus of cheerleaders chant: "I'm waiting for it, that green light. I want it."

The green light is a recurring theme in F Scott Firzgerald's The Great Gatsby, signifying the elusive promise of the future. Lorde may be referring to that or, more simply, a green light giving her permission to move on with her life.

The song's a grower

Structurally and thematically complex, Green Light isn't as immediate as previous Lorde singles like Royals and Yellow Flicker Beat. In particular, there's an awkward gear change from the haunting, dramatic verses into the choppy, beat-driven chorus. But in common with one of the year's other great pop comebacks - Katy Perry's Chained To The Rhythm - the song rewards repeated listens.

The cathartic music video, directed by Grant Singer and featuring Lorde dancing in strobing green lights and on car roof-tops, helps give the song some context, too.

It was co-written by this guy

Lorde's spent last year working on her new album with US musician Jack Antonoff. You might know him as a member of the group .fun, the band behind the 2011 smash We Are Young. You might also know him as the boyfriend of Girls creator Lena Dunham; as the co-writer of three songs on Taylor Swift's synthpop opus 1989 - or even through his solo project, Bleachers.

Either way, Green Light (along with most of Lorde's new material) was recorded in his home studio in Brooklyn, as pictured in this Instagram shot.

"We worked out of the house for the better part of a year, in this tiny little room covered in bizarre animal wall paper," she said.

Her fans are pretty pleased

From the teenagers who hid in the school toilets to hear the song premiere, to the fan who wrote "this was worth the million year wait", it's fair to characterise the reaction as "broadly positive".

Lorde's not sorry about disappearing for two years

The star was just 16 when her debut album was released

Last year, Lorde scolded an impatient fan who said he was "giving up" on the chances of hearing a follow-up to her debut album, Pure Heroine.

Speaking to Mistajam, she explained the extended break had been necessary.

"I needed to just go away, go home to New Zealand, and hang out by myself and figure out what I was going to do next. I knew I couldn't make the same thing again, and I had to figure out what it was that I wanted to say. And I'm so glad I took that time, because this record is the coolest thing I've ever made."

The new album will be called Melodrama

Lorde revealed the cover art on her Twitter feed

Earlier this week, eagle-eyed fans spotted the cryptic message "M*******A" in the title bar of Lorde's website.

They guessed, correctly, that this was a hint about her album title... with possible names including Macadamia (?), Mona Lisa or Musomania (an obsession with music).

But she's since revealed the record will be called Melodrama.

"I wrote this album about this crazy year of my life," she explained. "I partied a lot and I felt all the feelings - and it was all so fluorescent. So I decided to call the album Melodrama."

Green Light is the poppiest song on the album

"This is as pop-dance as it gets," she told Mistajam. "We were just in the studio, mashing around on the piano and... that's what it is."

"We didn't turn it into the single, it was just born that way."

The 20-year-old added the new album was more varied than her debut. "There's a lot of beats again but there's also instruments that are going to surprise people."

She might be playing Glastonbury

Fans have been chomping at the bit for Lorde's new album

Asked if she'd be visiting Worthy Farm this June, Lorde replied: "You know, farms are cool. I love farms. I'm a big fan of farms. So who knows?"

She believes we need musical catharsis

Lorde's biggest single to date, Royals, won two Grammy awards in 2014

A week into Donald Trump's presidency, Lorde posted a link to the album Sweet Sexy Savage, by US R&B singer Kehlani.

"After a horrifying, anxiety-inducing week of news, music like this allows much needed catharsis," she wrote. "I truly believe in the necessity of cathartic pop records in times like these.

"I love the big sprawling projects too, but there's something about the falls & lifts of meticulous pop, moments designed for u to feel what u need to, that's more important than ever.

"You're probably guessing what kind of record I've made based on these tweets."

We can't wait.

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