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Alexis Korner posing for a photograph in the 1960s.

In the cold light of today, Alexis Korner looks an odd kind of character. There’s a famous black-and-white photo of him in a striped shirt and tightly knotted necktie, holding a smouldering cigarette.

He’s got a long, mournful, serious-looking face, a big mane of tousled black hair and huge furry sideburns. He looks like a villain out of a 1960s TV thriller; the nemesis to Patrick McGoohan in an episode of Danger Man, perhaps. Or maybe the blunt-talking anchorman on a late-night intellectual series about the arts.