A drama centered on the relationship between Elliot Graham (Sir Michael Gambon), a strange and wealthy Londoner, and Joe Dix (Danny Lee Wynter), a teenager who takes care of an empty house Elliot owns.

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.