At the coast, two worlds collide. See how wildlife survives in this ever-changing world. It's a roller-coaster ride of heart-stopping action and epic drama.
The big blue is a marine desert, far from the shore, kilometres deep, with almost nothing to eat, and is home to some of the most spectacular creatures on Earth.
It's our green seas, not the blue, that bring life to our oceans. Here sunlight powers the growth of enchanted forests of kelp, mangroves and prairies of sea grass.
Examining the role of human anthropogenic activity on the oceans. Microplastics and pollution are an increasing problem for the world's seas, threatening the lives of marine life and ultimately impacting on the ecosystem.