A small, scaly baby iguana— no bigger than a chocolate bar— hunkers down on a beach as a snake glides alongside him. "A snake's eyes aren't very good," a raspy voice explains. The voice is British and immediately familiar. Comforting, somehow. "But if the hatchling keeps its nerve …" A low hum of strings rises in the score, and in a moment, the iguana begins a desperate, wild-legged sprint as percussion thunders.
One snake becomes three, six, maybe two dozen and the nightmarish reptile chase is on. If the newly born iguana makes it to high ground, it survives. If it doesn't, well, nature wins.
"Planet Earth II" is, at its core, the ultimate thoughtful celebration of life. Yet this frantic chase scene from the forthcoming series, which had the Internet buzzing, is more reminiscent of something out of the "Bourne" franchise.
The clip, which was released as a teaser for the series on YouTube in November, has racked up more than 3 million views since it became a viral fixture on Facebook and offered one of the first looks at "Planet Earth II," which debuts at 9 p.m. Saturday across three networks: AMC, Sundance and BBC America.
"The first time I saw [the iguana sequence] I just thought, I wish I had worked on a film where a director had created as exciting an action sequence as that," said Oscar-winning composer Hans Zimmer ("The Lion King"), who provides the series with a score that's as eclectic as the jaw-dropping scenery.
Already having aired in the U.K. late last year, the six-part sequel to "Planet Earth" reunites the voice of veteran naturalist and broadcaster Sir David Attenborough with far-flung locales and scenes of wildlife filmed with a startling intimacy that expands upon its 2007 predecessor.
"This is probably the most compelling emotional storytelling that I've ever been involved in," said Zimmer, adding that his admiration for Attenborough and his work assured his involvement with "Planet Earth II" from the moment he was asked.
"You look at our world as if it were a science-fiction movie," said the composer, who also has crafted Oscar-nominated scores for, among other films, "Gladiator," "Interstellar" and "Inception." "And then, every once in a while, you have to pinch yourself because you realize that everything that is strange and foreign and extraordinary is right here."
It's that eagerness to provide previously unseen glimpses of the natural world that drove the series' crew to log more than 2,000 shooting days in over 40 countries over roughly three and a half years. Like its predecessor, each episode is divided into geographic themes such as "Mountains," "Islands" and, in an intriguing look at the frontier between man and nature, "Cities."
With climate change still an ongoing concern amid political upheaval both in Britain and the U.S., "Planet Earth II" feels especially timely. But given the lead time and logistical demands of filming such a mammoth project, its creators had no way of predicting that would be the case.
"We were purely looking at the natural world and that sense of connectedness [with humanity]," said producer Elizabeth White, whose "Islands" episode opens the series. "It did feel timely that we wanted to try and reconnect people on a big, kind of global scale."
The first installment of "Planet Earth" offered up-close-and-personal looks at often unfamiliar wildlife and was among the first such documentaries to take advantage of HD video. (You couldn't go into a Circuit City at the time without seeing the series being used to showcase the hi-res power of Blu-ray.) The sequel ups the ante with 4K video, motion-triggered cameras and the use of drones, which helped deliver many of the breathtaking views: lemurs hopping from tree to tree in the jungles of Madagascar; a rare snow leopard protecting its offspring in the Himalayas; the battered coast of Zavodovski Island, which a million-plus Chinstrap Penguins call home.
"The challenge there was finding penguins who were happy for us to film around them," said White, who was on location at the island. "And then there was one who came out with this big, fat belly, and he was so chilled out. Literally, the camera man kind of walked with him, following him. He'd stop. He'd wait. You find yourself with an animal that seems very receptive to it."
Those dramatic narratives are what drive "Planet Earth II," a detail that helped inspire Zimmer. "You can really pour your heart into this. You can pour drama into this," he said, comparing his approach to "Planet Earth II," to working on the "Lion King" score. "You can tell the most amazing story about the human condition by not talking about the human condition."
The series premiere also follows a regal, pale-gray albatross — which mates for life — anxiously waiting for his partner to return after six months apart. While nature documentaries can easily fixate on the most harsh, unforgiving side of nature, this series aims to strike a balance.
"It would be wrong to tell that as a 'she never came back' story because actually in that case, that was what we wanted, to show this continuing relationship that can go on for decades," White said. "The film crew in many ways were going through the same sort of emotional journey [as the viewer] of, what happens if she doesn't arrive?"
In terms of attracting an audience, the sequel's reception has been overwhelmingly positive. The series finale averaged 9.5 million viewers in the U.K., outdrawing the finale of the popular competition show "The X Factor" ("We got something right!" Zimmer crowed). However, the series has drawn criticism for encouraging a sense of complacency about environmental issues. While each episode emphasizes that the habitats it examines are under threat, how dire can the situation be when they look so lush and beautiful?
"It's not a hammer-people-over-the-head, doom-and-gloom message," White admits. "It's very much 'Look at this wonderful place — Bear in mind, this is happening, these places are fragile' ... but it isn't intended to be a conservation film."
Still, there is a sense of having made a difference. As more people become familiar with breathtaking parts of the world, the thinking goes, the more people will work to protect them. White recounted multiple instances of meeting conservation officers on location who said they chose their career after seeing one of Attenborough's nature programs.
"I think it's quite hard to quantify what measures people take," White said. "But if they feel more connected to nature, that's a really good start."
'Planet Earth II'
Where: AMC, BBC America and Sundance
When: 9 p.m. Saturday
Rating: TV-PG-V (may be unsuitable for young children with an advisory for violence)
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