A BBC series on Leonardo da Vinci was a lot of sizzle without giving away much about who Leonardo really was. “Ever since the 15th century, it sometimes seems, programme-makers have been trying to fit art on to the small screen. Art is not natural television, as nature is. Few of us are ever likely to see the worlds revealed by the Blue Planet in any other way. We all, however, can go to an art gallery. As for seeing the Mona Lisa, we can hardly avoid it. So a programme about art needs a lot of insight and originality.”