Professor Brian Cox concludes his exploration of the way the underlying laws of nature shape the world around us with a look at how light interacts with our planet to create colour. As you’d expect, there are some spectacularly beautiful sights, such as the rare ‘moonbow’, a band of colours which occurs when moonbeams meet the spray of a waterfall. The professor also visits the warm waters of the Dominican Republic to find out why the planet looks predominantly blue when viewed from space, and asks why lava is red, plants are green, the sky is blue and the moon is red during a lunar eclipse. Fascinating stuff, and a glorious technicolour finish to a truly engaging series.