Brian Cox and Robin Ince are joined by comedian and musician Tim Minchin and oceanographers Diva Amon and Jon Copley to uncover what mysteries still lie at the bottom of our oceans. It is often said that we know more about the surface of the Moon then we do about our own ocean floor, but is that really true? What have modern-day explorers such as Diva and Jon discovered during their many expeditions to the deepest points of our oceans, and can they persuade Tim to join them on their next voyage? From extraordinary life forms with incredible survival strategies, to the gruesome sex life of the angler fish, the panel discuss some of the greatest discoveries of the last few years, and what questions they still hope to answer. Executive Producer: Alexandra Feachem