The corpse of a young girl was found on the roof of the house. According to the documents, the unfortunate woman is Elina Volodina. But it soon turns out that Elina is alive, and the deceased girl is her younger sister Valya Semyonova, who often took Volodina's passport to go to nightclubs. At the school where Valya studied, Pankratov and Bobrova talk with her friend Anfisa, who claims that Semenova led a quiet and measured life. But an analysis of Vali's internet communication suggests otherwise.