We call this 'pulling an Ellen'.

Last week, Mike Yung became an international sensation after a video of him singing 'Unchained Melody' on the New York subway went viral. And as is now the way with anyone who becomes famous via the internet, he made his television debut less than a week later, this time after James Corden found him and flew him all the way to Los Angeles to appear on 'The Late Late Show'.

And Yung's talents are just as good on live TV as they are 40ft underground.