We live in a world ablaze with colour. Rainbows and rainforests, oceans and humanity, Earth is the most colourful place we know of. But the colours we see are far more complex and fascinating than they appear. In this series, Dr Helen Czerski uncovers what colour is, how it works, and how it has written the story of our planet - from the colours that transformed a dull ball of rock into a vivid jewel to the colours that life has used to survive and thrive. But the story doesn't end there - there are also the colours that we can't see, the ones that lie beyond the rainbow. Each one has a fascinating story to tell.