In the English countryside, a scientific team testing a new biological radar (a system that can detect biological organisms in an environment) locks horns with a local coven of witches practising Black Magick. Fortunately, some of the members of the scientific team are psychics who know a thing or two about White Magick. Thus, their advanced technology can do little but record psychic fields as the forces of Good and Evil battle it out.
Author Stewart Farrar was the High Priest of a white witch coven, so this mildly entertaining novel is more of interest for its knowledge of occult ritual (it helps for the reader to have some basic familiarity with modern witchcraft) than it is for any thrills, especially for readers more attuned to violence and gore than more reasoned examinations of the occult. A little atmosphere would have gone a long way toward making this novel more memorable, but it's not bad for those who enjoy this kind of thing.