Vaults: Who are the band on the John Lewis advert?

The John Lewis Christmas advertisement has become the unofficial launching point for the festive season.

Frequently heart-warming (and heart-wrenching), the emotive films are always accompanied by a cosy cover version of a well-known hit.

This year, the song is Randy Crawford's One Day I'll Fly Away, performed by a relatively unknown pop trio Vaults.

Music reporter Mark Savage finds out where they've come from.