Amid the lush coastal tropics of an eighteenth-century South American seaport an unruly copper-haired girl and a bookish priest are caught in chaste ill-fated love affair. Sierva Maria the only child of a decaying noble family has been raised in the slave quarters of her fathers mansion while her mother resides on a faraway plantation. On her twelfth birthday she is bitten by a rabid dog and even as the wound heals she is made to endure therapies indistinguishable from torture. Believed to be possessed she is incarcerated in a convent where she meets Father Cayetano Delaura who has been sent to oversee her exorcism. As he tends to her with holy water and sacramental oils Delaura feels something immense and irreparable. It is love the most terrible demon of all.