Outside a hugely important fashion show in Paris there's a small, thin, hunched-over old man, shabbily dressed, as though he wouldn't know fashion if it leapt out from behind a bush and mugged him. He doesn't look as though he has a ghost of a chance of getting past the event gatekeeper when some higher-up Frenchman spots him, rushes out and whispers something urgently in the young woman's ear: "For God's sake let him in. He's the most important man on Earth."

And it seems that Bill Cunningham of the New York Times - no, I hadn't heard of him either - is the most important person in the world; or at least, in the fashion world. Bearing in mind that the fashion world (as this film shows) is not just swish shows in Paris, but clothes people actually wear - day after day after day, every waking hour. Bill doesn't seem to have time to eat, drink or sleep; on the evidence of this documentary footage, I'm not convinced he does eat, drink or sleep.

He's a great subject for a documentary: a towering figure in a field you probably didn't realise even existed; so weird, in a hundred little ways, that he resembles nobody else who has ever lived; yet very human, and impossible, utterly impossible, not to like.