 During one of Gogol's visions, Oksana (as it turns out later, a rusalka) appears.In exchange for Gogol's help identifying which of the rusalka is actually a witch, who drains her strength from drowned women, Oksana promises to help him in the investigation.Meanwhile, to Guro's surprise and fury, it turns out that similar murders took place 30 years ago and nothing was done to uncover them.