Lorde's new song, Green Light: All you need to know

Image copyright Getty Images Image caption Fans have been chomping at the bit for Lorde's new album

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.

Green Light is the start of a "new chapter"

"I am so proud of this song,"

. "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

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

Green Light starts out sombre, as Lorde recalls the beginning and 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, oh, 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 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 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 accompanying music video, directed by Grant Singer and featuring Lorde dancing in strobing green lights, helps give the song some context, too.

It was co-written by this guy

Image copyright Lorde / Instagram Image caption Green Light was recorded in Jack Antonoff's studio

Lorde 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 . You might also know him as the boyfriend of Girls creator Lena Dunham - or even through his solo project Bleachers.

Green Light, along with most of Lorde's new material, was recorded in his home studio in Brooklyn, as pictured in

.

Lorde's new album will be called M*******A

Not literally. But when you load the star's website, there's a cryptic message reading "M*******A" in the title bar (look at the tab in your browser), suggesting her album's title will be revealed letter by letter, Wheel Of Fortune-style.

If it's a proper English word, with no spaces, that could mean the title is Macadamia, Melodrama or Musomania (an obsession with music).

Other possibilities include Mea Culpa or Mona Lisa.

The only person who knows for sure (other than Lorde herself) is her mother.

"Whispered the album name to my mum in the car today," she

, sending fans into meltdown.

She believes we need musical catharsis

Image copyright Getty Images Image caption 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 to find out.

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