On the show they both co-host this morning we asked listeners to vote on one challenge Liam had to do to return the favour to Gemma for shaving 1D in to her head ( http://youtu.be/_bFhuqEqKlA ).Listeners voted for Liam to get down to Gangam Style. Move over Psy.Listen back to the show: http://www.bbc.co.uk/programmes/b01n3x44