Imagine...The Many Lives of William Klein

Alan Yentob, William Klein (BBC)

Nothing was unconsummated about The Many Lives of William Klein, the pioneering photographer, film-maker and Imagine subject.

Klein lacked the immediate warmth of that other New York photographer and recent documentary star, Bill Cunningham, but his work and personality offered more dimensions.

A soldier who quit America to become an artist in Paris, he was lured back to Manhattan by Vogue to shoot fashion as street photography, but found greater enrichment - and fame - by capturing the lives of regular people.

Now 84, he was still at it, snapping guests at the opening of a new Tate Modern exhibition about him from the cover of a mobility scooter.

Showing a harsher sort of disregard for social acceptability that seniority permits (he's not a Facebook or tearoom kind of guy), Klein bade the BBC cameras farewell by flipping the bird while illegally smoking in a New York taxi. It was a winning picture.