WHEN Sir David Attenborough sifts through the dozens of fan mail he receives each day, there is a theme that keeps repeating itself about what audiences want to see.
As the 91-year-old renowned naturalist tells it, viewers love the natural world but they also love an escape from the dramas of day to day life.
"I get a lot of letters - usually 20 or 30 letters a day and more when a series is on," he says in London.
"The overwhelming thing people say is when you have all the worries of the world … just to be able to look at something where human beings aren't the prime players, where there is beauty, wonder, astonishment, history, biology and above all truth … that's what they want to watch."
In Attenborough's latest masterpiece, the seven-part Blue Planet II, the beauty and wonder of life on the seas and oceans of the world is on display in all its glory.
More than four years in the making, the epic series covers every ocean with footage shot from coastlines to some of the deepest channels.
Clocking up more than 6000 hours of underwater filming, the team behind the series has captured a series of natural phenomena for the first time and made several scientific discoveries.
In one of a series of firsts, viewers are treated to stunning footage of giant trevally leaping out of the Indian Ocean to snatch birds from the air.
In another iconic scene, the filmmakers use a deep-sea submersible to capture marauding packs of Humboldt squid hunting in the deep seas off Chile.
From the clownfish that drags a coconut shell for miles so his mate has somewhere safe to lay her eggs to the tusk fish that uses boulder coral like an anvil to crack open clam shells, Blue Planet II is full of evidence of the intelligence of sea life.
Viewers of the series will be treated to remarkable footage from plankton blooms that spark feeding frenzies among dolphins and whales to the extraordinary broad club cuttlefish that pulsates to hypnotise its prey.
But for the veteran Attenborough, the series also comes with a message about the devastation wrought by humans.
Viewers are confronted with an emotional depiction of the impact of global warming in the first episode, when we see a walrus frantically trying to find space on a depleted ice float for her cub to escape polar bears.
In scenes shot on Australia's Great Barrier Reef, the third episode of the series charts the impact of coral bleaching in scenes shot near Lizard Island in 2016.
As world temperatures rise, reefs will be destroyed and species will be wiped out, Attenborough warns.
"We know that if it goes up by 2C, the coral will disappear, the little polyps shrink and the coral goes white," he says.
"That's the basis for a whole complex community, so it's not just that the coral goes but there are a whole range of creatures which depend on the coral. About two-thirds of the fish in the ocean use the coral as the nurseries for their young."
"We are losing a major important element in the sea which affects us directly."
Much of the publicity around the screening of Blue Planet II in the UK last year focused on Attenborough's warnings about the impact of plastic on life in our seas. It was even cited by the UK Environment Minister Michael Gove when he called for new limits on plastics. And the Queen this week announced that plastic straws and bottles would be banned from all royal estates after seeing the program.
Warning that we are slowly poisoning our oceans, Attenborough says the series shows some of the "tragedies" caused by plastic.
"We've seen albatrosses come back with their belly full of food for their young and nothing in it," he says.
"The albatross parent has been away for three weeks gathering stuff for her young and what comes out? … You think it's going to be squid, but it's plastic. And the chick is going to starve and die."
In another heart-wrenching scene, a pilot whale is shown carrying the carcass of its dead baby that Sir David says could have been killed by plastic-contaminated mother's milk.
Attenborough says there is an unavoidable message that comes from the series - "that the seas are very vulnerable and they are essential to our future".
But if his many fans are worried there is too much doom and gloom, there is plenty of joy and whimsy too.
Insisting the series is "not an axe-grinding exercise", he says he wants to show viewers the "extraordinary, mind-blowingly beautiful, complex, exciting, important places" that within our oceans.
"It's a privilege to see," he says.
It's a privilege that will be shared by Attenborough's many fans. In the UK, where the series screened on the BBC last year, Blue Planet II was the most-watched television event of the year.
Australian audiences are bound to be just as intrigued by the magic and beauty of the oceans that Attenborough leads us through.
BLUE PLANET, Saturday, 7pm, Channel 9
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