I spied Sam Smith a few weeks ago outside Topshop on Oxford Street in London, his height and trademark long black coat striking a formidable figure amongst the crowds. There was no entourage and no throng of autograph hunters surrounding him, but, as celebrity sightings go, it felt immediately A-List. 

Despite only releasing his debut album, In The Lonely Hour, in May, the 22-year-old singer/songwriter is already a major international star. Just ten weeks after release, the LP went platinum ...