You may think of the twilight zone as a frequently-revived TV sci-fi series, but it also refers to that deep, dark, mid layer of the ocean between 200 and 1000 meters, a part of the ocean that has been largely ignored—until now. A team of scientists from the Massachusetts-based Woods Hole Oceanographic Institute just flew to the Bahamas to study this mysterious place and the diverse creatures that live there.

Their trip is part of a six-year project using new technology to better understand the twilight zone before it’s too late. Recent research suggests there are more fish there than any other part of the world’s oceans, and it could be the next frontier for the fishing industry. Countries like Norway have developed technology that allows them to extract hundreds of fish at a time from these depths. As surface water fisheries decline, the Woods Hole scientists want to gather information to inform policies enabling the twilight zone to be fished in a sustainable way before it turns into a free-for-all that threatens the health and vitality of that part of the ocean.

The Ocean Twilight Zone project will involve a series of expeditions to different parts of the ocean where scientists are using remotely-operated vehicles and towing nets to collect DNA from the water and even diving in a submersible to see the twilight zone with their own eyes. The Bahamas expedition was funded by OceanX, and took place on their research vessel Alucia.

Watch the video above to go with Quartz News in a submersible on a deep dive into the Atlantic Ocean and learn more about how the twilight zone may be key to feeding and protecting the planet.

Quartz News is a weekly video series bringing you in-depth reporting from around the world. Each episode investigates one story, breaking down the often unseen economic and technological forces shaping our future.

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