The national treasure is back with a witty, warm televisual wonder, this time exploring the most populous and stunningly biodiverse continent. But where is the urgency about the climate crisis?The clocks change, the nights draw in, and along comes David Attenborough to ease those autumnal blues. Right on cue, he is here, narrating another magnificent series about weird and wonderful nature that allows him to say delicious, fantastical phrases such as “a special set of grasping belly fins”. The continent of Asia covers almost a third of the planet’s land area, and encompasses desert, forest, mountains and frozen wilderness. It is also the most populous continent, forcing humans and animals to coexist “in the most remarkable ways”. In short, it’s a place full of the kind of stories on which nature documentaries thrive, covering all sorts of terrain and ecosystems, and this first episode is an excuse to explore a massive swathe of water, with its 21 oceans and seas.As ever, this is a masterclass in television, in which every element is cooked to perfection: it is filmed beautifully, edited with wit, soundtracked with flair and narrated with warmth and authority. We see the “flamboyant” moorish idol fish – which will be better known to some viewers as the droll Gill from Finding Nemo – as it congregates in large numbers and is then hunted down by sharks. If watching with children, it might be wise not to point out that the resulting melee resembles a minion buffet. There are baby sperm whales, who are learning coordination skills by chasing mangrove seeds through the water; the adults sleep upright, and look like stray statues that have escaped from Easter Island. There are manta rays, with five-metre spans, which take themselves off to “cleaning stations”, where other sea creatures treat them to the equivalent of a marine spa day.