Synopsis

Here is a guide to the locations explored by the Oceans team in the Atlantic. This episode sees them undertake a perilous descent into a ‘black hole,’ seeking to understand just how distinct our planet's earliest oceans were 3.5 billion years ago. They will dive one of only two places on Earth where the oldest known life form continues to thrive. Finally, they face waters swarming with sharks, willingly acting as human bait.