The central island of Honshu is home to over 100 million people and its biggest city, Tokyo, is one of the largest urban metropolises on earth. But it has a wild heart with most of Honshu mountainous. As this natural history documentary reveals, this wilderness is home to an astonishing range of wildlife including black bears, monkeys, exquisite fireflies and even cow demons.

Hokkaido is Japan's northernmost, and wildest, island. It’s a place totally unlike the rest of the country. Every year, it swings from a bitter Siberian winter into the warmth of a Mediterranean-like summer, when the thaw reveals a landscape changed beyond all recognition. But, as this natural history documentary reveals, it takes tough animals and tough people to survive there.

In the far southwest of Japan, there is a chain of islands stretching towards the tropics. It’s a place where all life is influenced by the power of the sea, and volcanoes and typhoons are forces to be reckoned with. This natural history documentary begins at an island at the top of the chain and travels south, revealing unexpected stories of isolation, unique wildlife and unsolved mysteries.