George Ezra is the BBC Sound of 2014 nominee who came out of nowhere. Unlike your Sam Smiths and John Newmans, the 20-year-old University of Bristol dropout hadn't featured on a dance hit or released a mixtape; he simply appeared (helped along, no doubt, by the muscle of Sony Music and a publicist who also represents Lady Gaga), and finished in fifth place.

That's not to say Ezra is all industry hype. Although it would be foolish to think Sony isn't steering him towards a Jake Bugg-shaped niche – he has already been the "trendy" entertainment at a Burberry bash – he is surprisingly unpolished. Ezra's live act, displayed to great effect in the tiny Lexington, begins and ends with his guitar and his voice. His freakishly mature pipes, cratered and rusty, are paired with a scaled-down folk-blues palette that allies him with Tom Paxton and Arlo Guthrie. If his banter wasn't speckled with "innit"s and shoutouts to friends from his hometown of Hertford (who oblige by heckling relentlessly), Ezra could have been teleported from Greenwich Village circa 1962.

Consistently bilious lyrics suggest that, romantically speaking, he has been around the block more times than seems possible at his age. Ezra's speciality is the jealous put-down: Leaving It Up to You is a falsetto spitefest ("I've been told your new companion is successful and handsome and charming … your half-wit boyfriend"), and Drawing Board dispatches a rival to a baroque fate: "You said you needed a haircut/ I recommended Mr Todd." The a cappella closer, Did You Hear the Rain?, is so self-pitying ("You cause me to weep, you cause me to moan") that you're tempted to suggest he pull himself together, yet the gravelly desolation feels real.

Ezra is unlikely ever to be cool, but he's clearly his own person – and that in itself makes him worth watching.

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