Five billion years ago an asteroid crashed into the Earth. The impact tilted the planet at an angle of twenty three and a half degrees. This cosmic accident created the world we know today. Using the Sun as a guide, we set out on an epic global journey. In the Arctic, a polar bear family wakes to the first sunlight of spring. Will they find food before the ice starts to melt? Half a world away, an elephant mother and her calf must share precious water with a pride of lions. Will their uneasy truce last? For the final leg of the journey, we follow a humpback whale mother. She must keep her calf safe on their 6000 km migration to Antarctica. This remarkable breath-taking story is narrated by Patrick Stewart and filmed with high definition cameras to create an unforgettable journey through the changing seasons and daily struggle for life across our planet, from rarely seen stunning landscapes to the smallest details in the lives of our best loved, wildest and most elusive creatures.