The famous terrorist Sergei Bobrov, nicknamed “Razvodnoy,” meets his classmate Pasha Egorchenko, who was discharged from the army due to injury and has currently lost interest in life. Pasha hates the whole world and Razvodnoy invites him to join the ranks of the most mysterious group in the Zone - “Sin”. But there is a condition: Pasha himself must cross the Perimeter and locate the lair of local bandits. This story is a prequel to the end of the novel-duology about the stalker girl Yana Volkova.