Caroline Lea’s recent historical fiction, The Metal Heart: A Novel of WWII (2021) fictionalizes events on the northern Scottish islands of Orkney during the 1940s. Twin sisters, Dorothy and Constance, flea to a remote island said to be cursed after the death of their parents. Facing the brutal elements as winter descends, the sisters find their isolation invaded by a population of prisoners of war who are relocated by the British Army to Orkney in order to labor on a protective earthen barrier around the islands.