In a remote corner of the South Pacific, National Geographic Explorer Enric Sala – one of the world’s leading marine ecologists – leads an elite team into an isolated underwater Eden. Sharks reign in the southern Line Islands, where humans rarely visit and survival is still of the fittest. Completing a daring survey of life on the reef from the micro to the mega, the research team uncovers secrets in what could be the last unspoiled archipelago on Earth.