James and Danielle meet on vacation and fall in love. She's going to the dark North Atlantic bottom to find life. He's going to Somalia to find a terrorist but gets a dark cell.

In a room with no windows on the eastern coast of Africa, a Scotsman, James More, is held captive by jihadist fighters. Thousands of miles away in the Greenland Sea, Danielle Flinders prepares to dive in a submersible to the ocean floor. In their confines they are drawn back to the Christmas of the previous year, where a chance encounter on a beach in France led to an intense and enduring romance.

James More is a hydraulic engineer who has been taken hostage in Somalia by jihadist terrorists, who suspect he is a British spy. Danielle 'Danny' Flinders is working on an immersion project in the deepest waters of the oceans to demonstrate her theory about the origin of life on the planet. A year before James and Danny met on the coast and fell in love. Now, separated, Danny starts her dangerous dive to the bottom of the ocean in Greenland without knowing if James is still alive.