A year or so before the beginning of World War I, a young woman named Lisa la Giuffria is seduced by a white magician, Cyril Grey, and persuaded into helping him in a magical battle with a black magician and his black lodge. Grey is attempting to raise the level of his force by impregnating the girl with the soul of an ethereal being - the moonchild. To achieve this, she will have to be kept in a secluded environment, and many preparatory magical rituals will be...