http://www.youtube.com/watch?v=Sj757ishXnQ&feature=youtu.be&app=desktop
A face-down Sia performed 'Chandelier' on Late Night with Seth Myers last night, with a little help from Lena Dunham and that's what's happening in that video above, basically.
It's going to be either David Walliams or Dawn French for the UK one, isn't it?