Harry Styles and Millie Bobby Brown send Twitter into meltdown as they show off their wild dance moves at Ariana Grande's London concert

He's been busy filming his highly-anticipated new music video from his upcoming second album. 

But Harry Styles took a break from his busy schedule on Saturday night to attend the first UK show of Ariana Grande's Sweetener World Tour at The O2 Arena in London

Fans went wild after spotting The Sign of The Times hitmaker, 25, dancing and chatting to his pal and Stranger Things star Millie Bobby Brown, 15, at the performance. 

Party time: Harry Styles and Millie Bobby Brown were spotted dancing and chatting together at the first UK show of Ariana Grande's Sweetener World Tour at The O2 Arena on Saturday

Party time: Harry Styles and Millie Bobby Brown were spotted dancing and chatting together at the first UK show of Ariana Grande's Sweetener World Tour at The O2 Arena on Saturday

During Saturday night's concert, excited fans noticed the celebs and quickly took to social media to spread the news on the two stars partying together.  

One thrilled fan wrote: 'So Harry Styles and Millie Bobby Brown were chatting during a Ariana Grande's show??? I WOULDN'T SURVIVE IF I WAS THERE.'

While another gushed: 'People at tonights show were really breathing the same air as Ariana Grande, Harry Styles and Millie Bobby Brown...woah.' 

Spotted: During Saturday night's concert, excited fans noticed the celebs and quickly took to social media to spread the news on the two stars partying together

Spotted: During Saturday night's concert, excited fans noticed the celebs and quickly took to social media to spread the news on the two stars partying together

Fans go wild: One thrilled fan wrote, 'So Harry Styles and Millie Bobby Brown were chatting during a Ariana Grande's show??? I WOULDN'T SURVIVE IF I WAS THERE'

Fans go wild: One thrilled fan wrote, 'So Harry Styles and Millie Bobby Brown were chatting during a Ariana Grande's show??? I WOULDN'T SURVIVE IF I WAS THERE'

In videos taken by shocked concert goers, former One Direction star Harry can be seen leaning over and happily chatting to Millie throughout Ariana's showstopping performance. 

The pair were then videoed dancing together and making the most of the first show of Ariana Grande's Sweetener world tour in the UK.  

Social media users were thrilled at learning of the duo's friendship, with many having wild reactions to the videos. 

'Millie Bobby Brown is out here dancing at an Ariana Grande concert with Harry Styles. That is what you call success.' 

Friendly vibes: In videos taken by concert goers, former One Direction star Harry can be seen leaning over and happily chatting to Millie throughout Ariana's showstopping performance

Friendly vibes: In videos taken by concert goers, former One Direction star Harry can be seen leaning over and happily chatting to Millie throughout Ariana's showstopping performance

Loving it: Social media users were thrilled at learning of the duo's friendship, with many having wild reactions to the videos

Loving it: Social media users were thrilled at learning of the duo's friendship, with many having wild reactions to the videos

Harry's night out at Ariana's concert comes after his recent trip to Scotland. 

The singer was shooting scenes for his latest music video to accompany his new tracks on his upcoming second album. 

In November last year, Harry dropped the bombshell to i-D Magazine that he was hard at work on his new record.

'I’m making my second album right now, so I’m going to do that, read a lot, and see what happens', he teased.

'When I got the role in Dunkirk, it happened right at the start of my first album, so I had to stop everything for five months.'

New music: Harry's night out at Ariana's concert comes after his recent trip to Scotland. The singer was shooting scenes for his latest music video from his upcoming second album

New music: Harry's night out at Ariana's concert comes after his recent trip to Scotland. The singer was shooting scenes for his latest music video from his upcoming second album

His recent music video filming also comes just a month after he spent a reported £8million on a second London property after a series of extended trips to Los Angeles.

Previously, Harry hired a full-time bodyguard to protect him on the set of his film Dunkirk from swarming fans in July 2016.

The singer-turn-actor was said to be the only star on movie set to have a security guard by his side the whole time, according to reports at the time.

Meanwhile, Stranger Things sensation Millie has also had a busy schedule recently with the hit Netflix series releasing its popular third series last month.

Hectic: Stranger Things sensation Millie has also had a busy schedule with the hit Netflix series releasing its popular third series last month

Hectic: Stranger Things sensation Millie has also had a busy schedule with the hit Netflix series releasing its popular third series last month

Look pretty in pink like Millie in Rodarte

When the stars of Stranger Things hit the red carpet at the premiere of Stranger Things 3 in California and stealing the spotlight was none other than Millie Bobby Brown.

The young actress looked pretty in pink wearing a custom gown by Rodarte. The ballerina inspired mini features a gorgeous ruffle off-the-shoulder style, cute mini hem and that stunning floor length train that really packs a punch.

With the warmer weather now here, a mini is a must have for your wardrobe and why not make like Millie and pick pink?

Sadly her exact dress is bespoke meaning us mere mortals can’t get our hands on it, but you can steal Millie’s style with the help of the edit below and where Asos’ ruffle mini dress caught our attention…

* PRICES MAY NOT BE AS ADVERTISED

Harry Styles and Millie Bobby Brown send fans wild as they party together at Ariana Grande concert

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