While millions froze in October, rooting themselves to the spot for the Mannequin Challenge, two young men from Mississippi began to move very fast indeed.

Swae Lee and Slim Jxmmi, the brothers that make up the wavy hip hop duo Rae Sremmurd, burst to the top of the American charts with their song “Black Beatles” after it became the craze’s unofficial theme.

To some soundtracking a meme may seem like one-hit wonder territory, but to apply this label to Rae Sremmurd is to completely ignore their brilliant and infectious output over the last two years, how fresh and exciting their sound is, and their supernaturally energetic live performances.

The Sremm boys didn’t make “Black Beatles” the Mannequin Challenge soundtrack, but it was the perfect pairing.

Ever since their debut album “Sremmlife” came out in 2015, their work has bubbled with the internet, and the internet has bubbled with them. As well as having a huge online following, their lyrics are peppered with references to memes, including classics such as "get you somebody that can do both" ("Black Beatles) and "this could be us but you playin'" ("This Could Be Us"). It's not just any old internet that streams through their work, but the attention flipping, mobile-waving, follow-me-on-Instagram, Snapchat and Twitter one favoured by so many people today.

You can see this in the crowd at the Shepherd’s Bush Empire. Young fans, ready to party, wave their phone torches above their heads, with external battery packs on hand to ensure maximum coverage across their channels.

When the setlist opens on “Start a Party”, the room explodes, with the floor swirling and pushing back and forth. As the beat drops, so does Slim Jxmmi from the huge rectangular screen at the back of stage, while Swae Lee immediately leaps into the crowd.The duo rips through the song – and their entire set – with an intensity that ratchets up everything from their two albums, releasing all the energy impossible to capture in any studio recording.

The premise of most Rae Sremmurd’s songs are pretty simple – they love to party, have safe sex (“Wear Condoms” flashes up on screen towards the end) and don’t care what anyone thinks.

Combined with their embrace of social media, this removes all the barriers that usually come between artists and their fans. While they’re not rapping or singing, Lee and Jxmmi repeatedly go up to the crowd and take their phones. They film themselves, pulling faces for the front-facing cameras, before carefully returning each device to its owner.

Every song has its own accompanying visualisation, and on the screen they come together to form the world’s greatest Snapchat story, bursting with cartoon graphics and hallucinatory, Tumblr-esque visions. During "Come Get Her", Lee and Jxmmi become retro video game characters, while customised emojis punctuate songs like "No Flex Zone".

When it comes to “Black Beatles” at the end of the set, there’s no sense anyone has been twiddling their thumbs waiting for it. Songs like "No Type" and “Look Alive” have had the audience wrapped around a big Sremm thumb all night. The only thing missing is "This Could Be Us", which for some reason plays from the speakers once the gig is over.

But before it's all over, the arrival of the duo's biggest hit only furthers the crowd’s delirium, which has been peaking throughout the evening. On Jxmmi’s request everyone freezes, but the challenge quickly becomes too challenging. No-one can contain themselves and the floor erupts once again.