The plot may be divided into two sections: the story of a young couple and the story of a witch. It all begins with Andrey, a young architect, who comes to a mystical woman Mara, known to be a psychic, and asks for help. From his monologue we find out that some months ago he and his wife, Olga, became victims of a robbery. The villains had tried to rape Olga, while she was pregnant and so vulnerable, and actually caused her a lot of damage as consequenly she lost her baby. In the background of that tragedy Olga got psychological trauma and her relationship with Andrey was ruined. Besides, the main hero blames himself as he confesses of not being brave enough to save his love from such painful experience. That is why he asks Mara to help Olga forget that terrible accident, so he would be able to live with his wife happily again. Though Mara agrees and her motivation to help seems convincing, the intuition tells us that there's a trap. Mara uses the magic of funguses (from Russian mythology we may know that witches used funguses to fool and even kill people) and in one moment of time she ostensibly leaves the country and has no one to watch her funguses that are being grown in her flat. On this pretext she asks Andrey and Olga to move into her apartment for some time. After they do, terrible things start to occur. Olga sees ghosts that abduct her, but Andrey doesn't know how to save his wife until a strange little girl helps him to find the right way.
That girl was also the one to reveal Mara's story and motive to make Andrey suffer. Here's the second section telling us that a long time ago the evil witch was just a little girl who was stolen from her family during the Civil War in the beginning of the 20th century and made a mistress, though she was only about 10 years old. Mara recognized her own father who hadn't been brave enough to save his daughter from such terrible destiny in Andrey. Here is the point in which two stories are connected.