Subscribe and 🔔 to the BBC 👉 https://bit.ly/BBCYouTubeSub
Watch the BBC first on iPlayer 👉 https://bbc.in/iPlayer-Home Over half of all animals in the open ocean drift in currents. Jellyfish cross entire oceans feeding on whatever happens to tangle with their tentacles. The jelly-like Portuguese man-of-war can harness sail power to fish with its deadly tentacles.

The big blue is the world's greatest wilderness, far from shore and many kilometres deep. It's a vast marine desert where there is little to eat and nowhere to hide. Yet it's home to some of the biggest and most spectacular creatures on earth.

This episode reveals what it takes to survive in this savage and forbidding world. We witness feats of incredible endurance, moments of high drama and extraordinary acts of heart-wrenching self-sacrifice.

Blue Planet II | Series 1 Episode 4 | BBC One

#BBC #BluePlanetII #BluePlanet
All our TV channels and S4C are available to watch live through BBC iPlayer, although some programmes may not be available to stream online due to rights. If you would like to read more on what types of programmes are available to watch live, check the 'Are all programmes that are broadcast available on BBC iPlayer?' FAQ 👉 https://bbc.in/2m8ks6v.