Attenborough the Extraordinary shows us more wonder we could never have imagined: CHRISTOPHER STEVENS' five-star review as Blue Planet returns with a stunning third series

Published: 15:59 EDT, 1 November 2026 | Updated: 16:12 EDT, 1 November 2026 Blue Planet III (BBC1)Rating: Five stars Pub quiz question: What is the biggest city on Earth? The answer depends how you measure it: Shanghai is home to the most people at 25 million; New York covers more than 5,000 square miles; Tokyo is widest at about 100 miles across.But they are all dwarfed by the cities under the sea. Blue Planet III took us into the tropical coral reefs, unimaginably vast structures thousands of miles long, built by trillions of tiny inhabitants called polyps – a sort of miniature jellyfish that feeds on seawater nutrients and excretes them as particles of limestone.Water covers almost three-quarters of our planet – but that doesn't begin to convey the immensity of the habitat. On land, we all live at ground level, whereas the seas can measure miles from waves to bed and teem with life in three dimensions.It is mind-boggling. 'There are many more animals in the ocean than anywhere else on earth,' declared the unmistakeable tones of Sir David Attenborough, introducing the first episode of this six-part series – filmed across 100 expeditions, spanning four years and thousands of hours of high-definition video. Blue Planet III took us into the tropical coral reefs, unimaginably vast structures thousands of miles long, bigger than any of the large cities on landHis delivery is as sure and confident as ever, his timing perfectly weighted so that we have time to take in every fact. The script informs and entertains, giving context and meaning to what we're watching, but never obtrudes on the images.He sounds like a man half his age. What shines through is how fascinated he is by all kinds of animal behaviour. He is genuinely enthralled by what he's seeing, as much by the harlequin shrimp as by the sharks.For sheer ferocity, the shrimp's the winner. A pair of them went to work on a starfish, gnawing off one of its arms and carrying it back to their lair on the reef.For the starfish, this was an inconvenience but not a fatal one. It simply grew a new arm. If scientists ever work out how it does this, hip replacements might become a lot less bother.A dolphin had a devilish trick. She picked up sponges off the seabed and stuffed them into the crevices of the coral where her prey liked to hide – blocking their escape routes.But the most surprising technique was perfected by a shoal of slow-moving nurse sharks. These placid predators gather close to the shore, in groups of up to 40, and pretend to go to sleep. Sir David Attenborough's delivery is as sure and confident as ever, his timing perfectly weighted so that we have time to take in every fact Throughout his career, Sir David has sought new and unseen behaviour from the intrepid film crews, and once again the Blue Planet teams have delivered itGreat clouds of herring and silversides gather, oblivious to the danger as the tide goes out. With a sudden lunge, the sharks wake up and form a line, driving the little fish to the water's edge. All the hunters have to do is open their mouths and let their dinner jump in.Filmed from drones, the scale of the spectacle and its amazing choreography was revealed. Throughout his career, Sir David has sought new and unseen behaviour from the intrepid film crews, and once again the Blue Planet teams have delivered it.The editing is a delight, too. Shots are chosen that seem to show ocean life reacting in very human ways. When a fiddler crab wakes up to the lurking danger of a scarlet ibis patrolling the sands, it appears to throw up its pincers in horror. Its eyes, naturally standing out on stalks, make it look all the more alarmed.My eyes were standing out on stalks too. Every time you think Attenborough the Extraordinary has shown us all the wonders in the world, he presents us with even more we could never have imagined.