[Editor's Note, 01/27/17: Planet Earth II, narrated by Sir David Attenborough, will premiere Saturday, February 18 at 9/8c on BBC America, the US home of the BBC's landmark natural history series. The previous air date was changed after this article by Alex Strachan was posted.]

In the beginning there were the heavens and the earth.

Planet Earth II has come and gone on BBC TV in the UK, and word is, it was good. Not just good, in fact, but special, if you’re to believe media pundits on both the left — the Independent, the Guardian — and the right — the Telegraph, the Daily Mail, and so on.

And it’s not just media pundits, but audiences, too. Sir David Attenborough’s bracing, life-affirming view of the natural world drew audiences of up to 10.6 million viewers, a 40.2 percent audience share, across the UK — the equivalent of 50 million viewers in the US, the kind of numbers not seen since the golden age of the broadcast networks.

In his review of the opening scene — the very first scene — the Daily Mail’s Christopher Stevens described a hot air balloon floating like a snowflake above an alpine vista.

“It was spectacular," he wrote. “It was beautiful, it was magical.”

”As the pilot worked the burner, the sole passenger gazed over the mountains and turned to the camera with the smiling ease of a man who has been doing this for 60 years and more.

”And in living rooms across the land, millions of viewers stopped marveling at the frozen landscape and thought: ‘Sir David Attenborough is 90 — is it really wise to chuck him over Mont Blanc in a flimsy contraption like that?’”

There were more superlatives to come.

By the time the finale aired on Dec. 11, the Radio Times dubbed it “a truly epic achievement of broadcasting,” from the “pitch-perfect” musical score by Hans Zimmer to miraculous images of nature caught on camera every week, for six weeks.

This Planet Earth was more than just entertainment, however.

Attenborough once said — on 60 Minutes, no less — that he always avoided the message of conservation and environmental protection in his films because no one sitting at home wants to be lectured about how the planet is going to hell, “and it’s all your fault.”

Times have changed, though, and this Attenborough — Planet Earth II follows 10 years almost to the day after the original edition — has grown both older and sadder.

He is 90 now, and he’s starting to think not only about his legacy but also of the planet’s legacy.

In the final scene of the series, he stands atop the Shard in London, his white hair flying in a cold, stiff wind, and he tells his audience that it’s now down to us to save the planet.

Be responsible. Be active. Be aware.

That final episode, “Cities,” pointed the way toward a future where, counterintuitive though it sounds, many of the world’s remaining wild animals can only survive if they adapt to living in close proximity to humankind.

Planet Earth II makes its US debut on Saturday, Jan. 28, on BBC America.

And while it’s hard to imagine it having quite the effect on US cable television that it had on the UK’s public broadcaster — seen in every home — there are already signs that it will be one of the big broadcast events of the coming year.

Planet Earth’s selling points are well known. You will see things you have genuinely never seen on television before. The filming technology is, quite literally, breathtaking at times. Much of what you’ll see in Planet Earth II could not have been filmed 10 years ago, when its predecessor set a new standard in natural history documentary filmmaking.

It isn’t just TV, though — it’s something deeper.

Planet Earth II is a form of therapy for viewers, Attenborough has said, and he believes that to the depths of his soul. It offers viewers a respite from their worries about the world, by showing the natural world as it is — not in an idealized, anthropomorphized, Disney way, but through the scientific detachment of hidden, unseen cameras and microphones.

Planet Earth II was the most watched natural history show in the UK in 15 years. The morning after it debuted, Attenborough suggested to the Guardian that viewers were reconnecting “with a planet whose beauty is blemished, whose health is failing, because they understand that our own well-being is inextricably linked to that of the planet’s.”

The relationship, he continued, is a form of “two-way therapy.”

It’s not all doom and gloom. As the world emerges uncertainly into a new year beset by strife and environmental stresses, Attenborough asks us to imagine a world where pandas are no longer in imminent danger of extinction, and a vast expanse of the equatorial Pacific twice the size of Texas has been declared a marine protected area. Imagine a world where wild beavers now roam in Scotland for the first time in decades, where wild cranes are breeding in Wales for the first time in 400 years, and where more large blue butterflies are dancing across the UK than at any time since the 1930s.

That is not some Avatar-like fantasy world in the distant future.

That was the world in 2016, and Planet Earth II was there to record it.

Among the unique moments captured on film — moments that went viral, on YouTube and in other social-media forums — were a hatching iguana squaring off against a pack of racer snakes, a sloth searching underwater for a mate, a rare snow leopard searching the snow-capped Himalayas for her missing cub, and even dancing bears.

When nature is left alone, the Guardian’s environmental writer Patrick Barkham noted in a Christmas Eve column, it has remarkable powers of recovery — but none of these revivals happen by chance.

In the end, Planet Earth II’s most profound and significant message might be that we’re already learning to live with urban wildlife.

For all the words written about Planet Earth II, its real power, and the reason for all those viewers, lies in its visual beauty, its appeal to that which we can see with our own eyes.

Attenborough has often noted that the original Planet Earth, broadcast in 2006, was watched by an estimated half a billion people worldwide, and small wonder. It took us places, showed us things we had never seen before.

Planet Earth II takes that one step further, not with more of the same but with a picture of the earth as it might one day become, in the not-too-distant future.

If early signs count for anything — and sometimes they do — Planet Earth II already looks like one of the crowning broadcasting achievements of the New Year.