In the darkest hours of World War II, Doreen Valiente (then known as Doreen Dominy), an expert on British folklore and the occult, is approached by British intelligence at Bletchley Park who tell her they know she's a witch... and that's how she can best serve her country. Together with the 'most evil man in the world,' a hard-nosed white witch, the grizzled founder of Wicca, and a professional exorcist and con man, Valiente will travel deep into the heart of Nazi-occupied Europe and gamble her life, her belief, and her powers on a mission to help capture Rudolf Hess, second in command to Adolf Hitler himself.