Submergence (2017)

Two people remember a passionate romance that began on a beach during Christmas a year prior while experiencing completely different forms of fear, exhilaration and triumph half a world away from one another. James Moore is an Englishman who jihadist fighters have taken captive somewhere on Africa's eastern coast. He exists in the darkness. Danielle Flinders is a deep sea explorer diving in a submersible near the ocean floor in the Greenland Sea. She too exists in darkness. Both survive in different dark seas through memories of their love and Dany's description of what it is like to dive inside of a submersible.