The first thing that often springs to mind when the word “K-pop” comes up is usually an image PSY dancing along to his mega-hit, Gangnam Style. But there’s so much more to the world of South Korean pop music, a curious and slightly terrifying musical genre that has its own strange rules, conventions and customs, whose “idols” are venerated like gods in their own country but – for the majority of people – go unrecognised outside of Asia.

But that’s starting to change, thanks to one super group who have just set out on a sell-out world tour, including two dates in London in October that sold out in a matter of minutes. In May the pop music juggernaut known as BTS became the first K-pop band to top the US Billboard album chart.

More recently they obliterated Taylor Swift's record for the most-viewed video in 24 hours, with a staggering 45 million views of their clip for their new single Idol - which is also due to become their first UK top 40 hit when the charts are announced later this week. In May

As the music industry laments limpid record sales, BTS’s business is booming: they sold 1.6 million copies of their fifth studio album in February 2018, a record in South Korea. That month they were also the first K-pop act to get a gold record, selling more than half a million copies of their song, MIC Drop (Remix). They were the first K-pop song to cross 50 million listens on Spotify in 2017, and continue to break records almost on a daily basis.