Part One of Two. UK two track CD pressing of the first single pulled from her 2007 album X. '2 Hearts' was written and produced by London-based Electro group Kish Mauve. Writing of the song, The Sun's Victoria Newton recently said: 'It is a sure fire #1, a classic Kylie song you won't stop humming.' Features '2 Hearts' plus the non-album track, 'I Don't Know What it Is'. EMI.