It was like the terror of a thrill-park ride, one that usually came with the implicit knowledge of safeguards and constraints. In the end, the adorable creature would survive. This was the compact. The animal that you liked would be OK. After all, this was TV.

There is one of those scenes in the second episode of “Our Planet,” the remarkable docuseries on Netflix. But now the compact is gone. A teeming colony of walruses is crammed at the edge of 80-meter cliffs along the coast of Russia, where climate change has melted away the sea ice. Not evolved to navigating the precarious surfaces, one walrus falls, and another, and another, their massive bodies slamming onto the rocky beach.

They do not, most of them, get up and shake it off. Their broken bodies litter the shore. This is the resounding message of “Our Planet”: It will not, necessarily, be OK. And humans — the unpictured but omnipresent part of “our” in “Our Planet” — are the reason.

“Our Planet” is the latest in a series of big-budget nature spectacles (“Planet Earth,” “The Blue Planet”) that use technology, enormous crews and patient observation to capture stunning, lapidary images from around the world. They’re the sort of color-saturated landscape art that makes your TV into a wonder box, the kind of video just begging to pulse from a wall of new model flat screens in a big-box appliance store.

These series are often conservation-minded. Certainly, they’re meant to inspire an awe for Earth’s delicate systems.

But intentionally or not, they may have had a kind of palliative, denial-enhancing effect, offering adults a version of the reassurance that older films offered children: The planet that you like will be OK. Yes, yes, climate change is real, forests are being razed, the Earth is slowly braising — but there’s still so much beauty out there! It’s fine! We’re fine! I saw it on TV!

The revolutionary thing about “Our Planet” is how it subverts this genre by following its structure and expectations. It’s organized on a familiar pattern. After an introductory episode, the following seven each explores a different type of ecosystem (forests, desert, the high seas), from the tiniest creature to the apex predators.

It’s awe-inspiring and easy on the eyes. Leafcutter ants pour over the rainforest like an armada of green-masted ships. An orangutan flips through the tree canopy to a jaunty caper-movie soundtrack. Dolphins athletically catch flying fish, which spew from the waters in a Busby Berkeley production circle. Kelp tower in a fantasy undersea forest like something off the cover of a progressive-rock album.

Mute the narration, and you could be watching the same screen saver art pageantry of a dozen past nature series. But the form of the episodes introduces this program’s mission. Each installment is about the web of life in a place — how the food chain that sustains a Siberian tiger begins with pine cones on a forest floor, how life in a river depends on steam rising from trees hundreds of miles away. Disrupt one part — raise the temperature, plant crops in a rainforest — and you disrupt them all.

“One Planet” appeals to the sense of wonder as viscerally as any of its predecessors, but to a purpose. Here is this beautiful, rare thing, each episode says. It didn’t used to be rare! But it is now. And here is how we’re responsible. And here is a tangible thing we might do to fix it. The arc of each installment runs from beauty to loss to a concrete, hopeful example of a battered ecosystem that’s recovered.

The series steers between didacticism and denialism with the narration of David Attenborough, the 92-year-old veteran of nature filmmaking. The familiar wonder and mirthfulness of his voice has a note of rueful loss. He carries his kindly-professor authority quietly. He’s not angry with us, just disappointed.

The understatement is potent. Attenborough describes a mating scene in a lush Madagascar jungle with typical verve, then drops a bomb: “Since these pictures were recorded, this forest, and the unique life it once contained, have disappeared altogether.” That celebration of life you thought you were just watching was, in fact, a funeral.

His voice-over is paired with images of destruction that are as breathtaking in scale as any mass migration footage. Satellite images of verdant green shrink to desiccated brown over and over. The rainforests episode closes with an aerial image of the wild Amazon tree canopy butting up against a homogeneous sea of agricultural palms, as sterile and monotonous as a computer-generated pattern.

It’s something I can hardly recall seeing in any TV wildlife spectacle: images used not just for the emotional gee-whiz factor but for dry commentary and damning visual irony. And it all builds to a series-ending sequence — I’m not used to saying “spoiler alert” for nature films, but I feel I should here — that I suspect will haunt me for a long time.

The last episode, “Forests,” winds up, of all places, in the ruins of Chernobyl, still depopulated after the 1986 nuclear disaster. The accident was a catastrophe, of course, for humans. But not for everyone.

The camera pulls back from an empty building, its Cyrillic letters crumbling — and there are trees growing from the roof. Everywhere in this desolated settlement, the forest, whose decline the episode had just detailed, is reclaiming its space. Hares and lizards scamper about the ruins. A fox creeps through an open entryway. A moose strides past a sign marked with the radiation symbol. Herds of endangered Przewalski’s horses roam wild.

Reader, I laughed. This vista was horrible, of course, apocalyptic, something from “The Walking Dead.” And it was amazing. We were gone, and life was springing back without us. This was the happy ending.

Whether a happy ending is still possible with us is the question “Our Planet” will leave you to sit with long after it ends.

This article originally appeared in The New York Times.