The most spectacular and ambitious series in television history finally screens in New Zealand this weekend.
On Sunday night, Sir David Attenborough will introduce Planet Earth II, the BBC's epic natural history show that took more almost four years to bring to the screen.
A decade after its predecessor attracted audiences of more than 11 million, Prime's series is tipped to prove another ratings triumph.
And the corporation has spared little expense, spending millions on cutting-edge technology to delve into unknown corners of the natural world.
The first series took five years to make and at £8 million was the most expensive nature documentary ever filmed by the BBC. It went on win an Emmy award and be shown in over 130 countries.
The new show's producers have described the great lengths taken to make sure the second series is even more spectacular.
Episodes were filmed in ultra-high definition by six separate teams gathering ground-breaking footage from around the globe. They managed to film four snow leopards together in the wild for the first time, as well as baby iguanas battling hordes of hungry snakes and a sloth going for a swim.
New technology has allowed the teams to bring viewers further into the animals' worlds. Gyro-stabilised cameras allow cameramen to move at speed alongside the animals, and drones captured aerial action sequences. Advanced camera traps were placed so close to wild animals that they even captured the sound of breathing.
The first episode looks at remote islands which offer sanctuary for many of the planet's strangest and rarest creatures, including New Zealand's Sub-Antarctic Snares Islands where we meet the nesting Buller's albatross, thriving in predator-free isolation.
The episode also captures the rare pygmy three-toed sloth enjoying a peaceful existence on an idyllic Caribbean island and features the scene as a young marine iguana tries to escape deadly racer snakes on the Galapagos Islands.
The BBC is hatching plans for a third series its ground-breaking nature show - and they want it to be made before David Attenborough's 100th birthday.
Now 90, the broadcaster has a decade to go before that landmark.
Planet Earth II took more than four years to produce, arriving a decade after the original, which screened in 2016.
If the BBC was to keep with the format, Planet Earth III would arrive in 2026, marking Attenborough's centenary.
Producer Mike Gunton deemed the host irreplaceable, saying: "It's pointless trying. We love working with Sir David and I think he loves working with us, and we want that to last as long as possible.
"When he decides he doesn't want to do any more, we will have to rethink how we make these programmes."
The BBC has previously tried to replace Sir David. In 1992, the newly-appointed head of the broadcaster's Natural History Unit, Alastair Fothergill, was told by chief John Birt: "Get me a new Attenborough."
In an interview last year, Fothergill said: "I never had the nerve to tell him, but I remember thinking, 'That's just about the most stupid thing I have ever been asked to do,' because there never will be one."
• Planet Earth II starts on Prime on Sunday, July 9 at 7.30pm