In Herefordshire's hop-growing country, a converted kiln is the scene of a savage murder. When the local vicar refuses to help its new owners cope with the aftermath, Merrily Watkins is sent in by the Bishop of Hereford to defuse the situation. Merrily, however, is already contending with a woman's claim that her daughter is possessed by evil. In both cases Merrily remains unconvinced, but nothing is ever quite what it seems. As she is drawn into a tangle of trickery, deceit, corruption and sexual menace, her hastily conducted exorcism produces unhappy results. With her career now on the line, she tries to uncover the secrets of Knight's Frome - a village concealing a twisted past . . .