The team explores a corner of the Atlantic Ocean. This ocean is the youngest of the great oceans and critical in influencing our climate.

Expedition leader Paul Rose, environmentalist Philippe Cousteau Jr, maritime archaeologist Dr Lucy Blue and marine biologist and oceanographer Tooni Mahto make a dangerous dive into a 'black hole' to discover how different our planet's earliest oceans were 3.5 billion years ago. They dive one of only two places on the planet where the oldest life form on Earth still survives: stromatolites, the creatures responsible for transforming our ancient oceans by producing oxygen.

They brave waters teeming with sharks to act as human bait in an experiment to test a shark repellent. They also investigate how the Atlantic has been invaded by the poisonous lionfish, which is decimating local fish stocks and spreading fast. And they try to identify a lost British warship, the HMS Southampton, which was shipwrecked after winning a battle against an American vessel in the war of 1812. Show less