Image copyright James Medina

After a build-up that can only be described as "epic", Harry Styles has premiered his first solo single on BBC Radio 1.

Titled Sign Of The Times, the majestic ballad is his first material since One Direction declared a hiatus in January 2016.

Here's everything we know about the song...

It's about the end of... something

Image copyright PA

What's it about? To be honest, we're not sure. The lyrics are a bit of a riddle.

"Just stop your crying, it's a sign of the times," sings Harry as the song opens. "Welcome to the final show, hope you're wearing your best clothes."

It's about the end of something, then. But what? A relationship? A boyband? An episode of Sherlock?

Harry's not telling. But he offers some hope towards the end: "We could meet again somewhere, somewhere far away from here."

It sounds a bit like David Bowie

Image copyright Reuters

Honestly, we're not making this up.

Although it begins with a series of sombre piano chords (Harry's been practising in private for years), the chorus soars like a miniature Life On Mars, replete with slide guitar riffs and impassioned vocals.

It threatens to collapse under the weight of its ambition towards the end, though, piling on more bells and whistles than a clown convention.

Seriously, was that choir necessary?

It's not the Prince song

Image copyright Reuters

It might share the same name as Prince's three-decade-old classic, but that's where the similarity ends.

Although Harry received a bit of flak from Prince fans, Sheena Easton, who duetted with the star on U Got the Look, says the Purple maestro would have approved.

"I'm sure he doesn't mind," the Scottish-born singer told the BBC. "Prince was such a giving, loving person, I'm sure he's up there saying 'go for it'."

Prince might not be so happy that the final 30 seconds are a carbon copy of Purple Rain, though.

He's feeling a bit nervous about the whole thing

Media playback is unsupported on your device Media caption Listen to Harry's full interview with Nick Grimshaw

He told Radio 1's Nick Grimshaw: "It's a bit weird. I feel like I've been hibernating for so long... and now it's time to give birth

"It's the song I'm most proud of writing."

You can hear it now

Image copyright Columbia

Shortly after the song premiered on Nick Grimshaw's Radio 1 show at 08:00 BST, Harry helpfully uploaded it to Spotify, Apple and YouTube... All five minutes and 40 seconds of it.

That makes it a full 70 seconds longer than anything One Direction ever recorded.

It links Harry Styles to Kanye West

Image copyright Reuters

Harry's co-conspirator on this track is Jeff Bhasker. You might not have heard of him but, since connecting with Kanye West on 2008's moody 808s and Heartbreaks album, he's become one of the industry's most in-demand writers and producers.

He co-wrote Uptown Funk with Mark Ronson and Bruno Mars, and his other credits include Jay-Z's Run This Town, Fun's We Are Young and Lana Del Rey's National Anthem - itself a clear influence on Sign Of The Times.

Speaking to GQ in 2013, Jeff explained his theory of pop: "You have to have substance. The best art and music comes from a combination of vulnerability and confidence, where you're opening yourself up. The artists know who they are, and when they deliver that song, people believe them."

He's the only person who can dethrone Ed Sheeran in the charts

Image copyright AFP

Ed Sheeran is on course to score his 13th week at number one with Shape Of You later today - but he should savour his last taste of the top, because Harry is almost undoubtedly going to unseat him next week.

Bookmakers have given Harry odds of 1/1 of scoring the number one next week - and 10/1 for having the best-selling single of the year.

He risked his life for the video

Image copyright Twitter

Harry was seen dangling from a helicopter off the coast of Skye as he filmed the video earlier this week.

It seems likely the clip will continue the watery theme of the single's artwork, which sees Harry wading through the sea towards a ghostly, submerged figure (Please, please let it be Leonardo Di Caprio).

The video was directed by French film-maker and musician Yoann Lemoine, who previously made promos for Katy Perry's Teenage Dream and Drake's Take Care.

Harry's been working on this material for five years

Long before One Direction called it a day (temporarily), Harry was in the studio writing with future collaborators.

In 2013, we spoke to Snow Patrol frontman Gary Lightbody, who'd recently spent a week in the studio with Harry and U2 producer Jacknife Lee.

"Harry loves Frightened Rabbit, so his music taste is very varied, it's not just pop," said Gary.

"We did four tracks together and hopefully some of them will see the light of day, because they're great tracks. He's got a great voice, he's the real deal."

He got the seal of approval from Ed Sheeran

"I played [Ed] a few songs after the album was finished," Harry told Radio 1.

"He didn't say that he didn't like any - but he did like one song that isn't on the album. So I did have a bit of a minute of, like, 'hmmm…'"

He will perform the song for the first time next weekend

US fans can tune into Saturday Night Live on 15 April to see him in action, while UK fans can catch him on the Graham Norton Show on BBC One on 21 April.

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