TORONTO -- Bears busting a move in the Canadian Rockies and a rascally raccoon family in Toronto are among the animals profiled in "Planet Earth II," the followup to the massively popular 2006 TV series that won four Emmys.
Debuting Saturday on BBC Earth, the visually arresting six-part series was filmed in 4K in 40 countries over a span of three and a half years, featuring exotic jungles, deserts, islands and grasslands.
The second episode visits the Alberta Rockies and shows grizzly bears coming out of hibernation and doing a dance against trees to scratch themselves.
Filmmakers captured the footage by installing cameras up high in trees that were identified by scientists as being among the type that bears like to use. They left the cameras there for several weeks and came away with intimate and hilarious footage.
"It's funny, that sequence feels a bit voyeuristic," said Elizabeth White, producer of "Planet Earth II."
"The way they get into their dancing, it really looks like these twerking bears. It was a really fun one in the edit, they put some great music to it. It's a side of bears that you wouldn't expect to see."
The raccoons are seen in a city-focused episode as they navigate the streets -- and garbage bins -- of Toronto late at night.
"I think we just wanted to show a parental struggle," said White. "It's an adorable story. It's a mother looking after her little ones and trying to look at the city through their eyes."
Hans Zimmer did the score and English veteran broadcaster David Attenborough narrates the series, which offers new perspectives on animals and the planet using sophisticated technology, including drones and thermal-imaging cameras.
The series offers rare footage, including river dolphins deep in the Amazon, female birds of paradise in the jungle, and adult chinstrap penguins feeding their chicks on the remote island of Zavodovski.
The first episode features island life and White said they had to battle El Nino during filming, but added that it "was relatively easy in that a lot of island animals are quite naive to humans."
"They're not used to human beings and so they don't feel massively threatened by them," she said.
The island episode starts with a story of a sloth who swims great lengths to find a mate. It also shows a fierce komodo dragon battle and a slew of snakes hunting down a hatchling marine iguana.
The high-stakes snake-iguana sequence has gone viral online, with over nine million views on the BBC Earth YouTube channel.
"We knew that snakes hunted iguanas but we had no idea we'd see such big numbers of snakes, so that's quite a spectacular piece of footage," said White.
"Even though behaviourally it's not actually a new revelation, it's a twist on a revelation of something we knew but didn't quite know."
White said producers go into filming with an idea of the drama they want to capture, but don't always come away with it. In the sloth sequence, for example, they were hoping to capture a successful mating effort but alas, the love was unrequited.
The creators consult with experts in order to make sure they're respecting the animals and their natural habitat, she said.
"There are rules and regulations, so you have to work within the framework of our own ethical code and also the people who you're working with," said White.
"So we've almost always got a scientist or a ranger there who is an expert in that location or that animal."