In 1890, King Leopold II of Belgium suffers from visions of the black people he killed in the Congo. He keeps his condition hidden from almost everyone else, including his wife, Marie Henriette. However, he enlists the help of a Jewish inventor named Travert to rid him of his visions. Travert presents Leopold and his entourage with a machine called the Variable Pressure Ethereo-Vibrative Condenser, which uses a process called vulcanization to make the ghosts haunting a person's psyche real so that they can be eliminated. To demonstrate the efficacy of his machine, Travert places a black girl whom he calls Fifine in a cage. The machine reveals some of the bird spirits occupying Fifine's consciousness. After the birds have become material, Travert kills them, eliminating them from Fifine's memory. Satisfied with the machine, Leopold enters it himself. As Fifine did, Leopold is unconscious once the machine starts running. He sees a young British girl, Lucy, who was killed in an attack he ordained against some rebels in his territory. She jeers at him, telling him that he won't be able to eliminate his spirits so easily. Whereas Fifine had a good relationship with the spirits of her memory, his crimes will keep him haunted forever. Leopold retains consciousness and finds himself surrounded by the same spirits as always. The machine did not work on him.