Ioana Nagy, a young midwife in rural Transylvania, has been accused of being a witch. Periodic precognizant revelations and her ability to discern spirits inciting humans to do evil make Ioana wonder if the accusations are true. Ioana struggles to support herself and her widowed mother in the economic turmoil following the end of communism and laments the disappointments of her life. But she senses big changes coming.

Gideon Hunt, a young, idealistic, and naive American missionary, arrives determined to prove himself by dispelling superstitions widely held by rural Transylvanians. He finds himself both drawn to and repelled by the strong-willed and capable Ioana, reputed to be a witch. Gideon's preconceived ideas about the supernatural are soon challenged by unworldly experiences.

As hateful presences deceive humans into committing despicable acts, Ioana and Gideon strive to define their relationship, understand spirits in the context of folklore, and protect potential victims. The arrival of a powerful demonic lord who rallies the forces of evil pushes them to the limits of their courage.