The Best Episodes Written By Sian Ejiwunmi Le Berre

When 18-year-old Rowan Edwards is found dead, DCI Ellis is called on to take over the investigation. She digs under the surface and sees that the town's parents know nothing about the lives of their children.

The underwater volcanoes turn out to reveal a clue to the legendary underwater city of Atlantis. A small group goes exploring and finds what appears to be an ancient outpost of the lost civilization, but also realizes that it is home to terrifying sea lilies and the crew must fight for their lives.