Makar Ilyushin and Sergey Babkin face a new challenge in their careers. They investigate a story about how noble goals can lead to tragic consequences, and how the best qualities can turn into sins. A sad melody sounds over a quiet town when the Ratcatcher leads a horde of rats.
Meanwhile, a young man with a guitar on the highway leaves his marks on the backs of girls, destroying them.
What connects these two people who crossed centuries, in their drive for destruction?
Sergey and Makar follow an investigation that turns into a chase after a ghost from the past. They throw logic out the window and rely only on their intuition.