When “Planet Earth” premiered in 2006 on Britain’s BBC One, it was the most expensive nature documentary series ever made, and the first to be shot entirely in HD. It was also a ratings bonanza. The first five episodes averaged 11.4 million viewers in the U.K. alone.

So why did it take 11 years to get a sequel on the air?

“These guys don’t want to make these shows just for the sake of making them or just for the sake of a large audience,” says Sarah Barnett, president of BBC America, where the miniseries will make its U.S. television premiere on Saturday night. “They’re driven by wanting to tell the best stories that they think they can tell.”

The first “Planet Earth” was remarkable largely because of its innovative use of HD cameras. “Planet Earth II” was sparked by further advances in camera technology that would allow the filmmakers to tell a more intimate story.

Like the original, “Planet Earth II” focuses in each episode on a different biome — this time islands, mountains, jungles, deserts, grasslands, and cities. In each, the camera attempts to present a perspective near that of the wildlife being documented, be it crabs fending off crazy ants on Australia’s Christmas Island or monkeys leaping from rooftop to rooftop in Jodhpur, India.

“When you watched the original ‘Planet Earth,’ you know that you were watching ‘Planet Earth,’” says executive producer Mike Gunton. “Afterwards there were a lot of copycats. That stand-back, look down on the planet perspective became quite familiar. We began thinking, ‘Where’s the different perspective?’”

At the same time, some of the original production team began expressing interest in crating a documentary that would tell the story from the animal’s point of view rather than the observer’s perspective.

“When those two things doubled along together with the miniaturization of the cameras that we used in the first ‘Planet Earth,’ when you could take that stabilized camera and give it to a cameraman and start to get in the animals’ world with a camera, that’s when we got that perfect alignment that generated ‘Planet Earth II,’” Gunton says.

The sequel was three years in the making and, like the original, is narrated by revered British naturalist David Attenborough. (U.S. viewers, who for some reason got an alternative narration from Sigourney Weaver when the first “Planet Earth” premiered on Discovery Channel a decade ago, will this time get the full Attenborough). Also like the original, it was a huge hit. The U.K. telecasts averaged 11.9 million viewers.

The first episode of the U.S. version will be simulcast across BBC America and corporate kin AMC and Sundance TV on Saturday night, in the hopes of giving it a broad platform. Subsequent episodes will air on BBC America. Barnett is hopeful that the series can draw new viewers to the network. She points to the phenomenon that the miniseries became in the U.K., with local pubs and soccer clubs hosting viewing parties — all on the heels of the divisive Brexit vote in Britain.

“It’s a remarkable show, and the story it’s telling is emotional and profound and fascinating,” Barnett says. “But on top of that, I think it landed at a time of unusual division and in a sort of moment, I think, of people not feeling that they’re on the same page about a number of things. And I think there’s something about nature that is a great unifier. I think there’s something about watching this kind of content that connects you to something kind of elevated. I think that at some level we’re all craving that.”