The young deacon Peter's father, the rector of the old church in the provincial Danilovo Posad, is dying. Unexpectedly, instead of Petya, Father Dmitry from Moscow is appointed the new rector. Petya does not trust the visiting priest and begins his investigation. which leads to a terrible discovery: Father Dmitry is a real devil, and he was in this parish for a reason. To protect his temple and the city, Petya enters into a battle with evil.