"Unlike the animals living on land or flying in the sky, the creatures in water usually pay less attention to such machines. The pivotal moment for a successful shot depends on the mood of the animals or how good the weather is," Yu says.

For most audiences who have already watched some aerial shots of natural resource-rich regions in previous works, the new season of the series might be a fresh experience to look at densely populated metropolises from a great height. Despite facing regulations in using drones to take photos from the sky in Hong Kong and Macao, the crew came up with a solution: When the drones snapped some interesting activity from the sky, the production team would contact the organizers of such events to see if they could be informed in advance the next time to obtain more footage.

In an effort to fully demonstrate China's huge transformation over the past decade, the documentary series consulted experts from different fields such as geology, climatology, archaeology and ethnology to help select the most attractive shooting sites, with a ratio of 10:1, or shortlisting one final shoot location from 10 candidates.