A Perfect Planet

G Volcanoes are the planet's most powerful force - and the most dangerous. Several times in Earth's history, volcanic activity has brought about mass extinctions. Yet, as this episode reveals, without volcanoes there would be no life at all.

G From the frozen poles to the searing deserts, this episode shows how animals have come up with strategies to survive the uneven amounts of sunlight that fall on our planet.

G Water is vital for all life. Our perfect planet has this important resource in abundance - yet most of it exists as sea water, too salty for terrestrial life to use. This episode looks at how weather controls the distribution of precious freshwater on Earth.

G Oceans are the largest ecosystem on Earth, covering two thirds of our world's surface. They're home to as much as 80% of all life on our planet, and nearly three billion people rely on them for their primary source of food.

G Series Finale: Our home, a blue glowing beacon of life, hangs alone in the cosmos. The only living world we know of. Life on our planet is shaped by the Earth's natural forces, but there is a new force, one so powerful, it is upsetting the balance of life on Earth and threatening our perfect planet - that force is us.