Imprisoned in a remote Turkish POW camp during the First World War, two British officers, Harry Jones and Cedric Hill, cunningly join forces. To stave off boredom, Jones makes a handmade Ouija board and holds fake seances for fellow prisoners. One day, an Ottoman official approaches him with a query: could Jones contact the spirits to find a vast treasure rumoured to be buried nearby? Jones, a lawyer, and Hill, a magician, use the Ouija board - and their keen understanding of the psychology of deception-to build a trap for their captors that will lead them to freedom.