Pensioner Vasilisa Yegoryevna contacts the agency with a request for help: she believes that her grandson is unfairly serving his sentence for the murder of his neighbor. After all, in fact, the neighbor is alive. At the same time, Danish citizen Lars Lange was killed in his hotel room. Investigator Borodulin suspects that the foreigner was a client of the Beagle agency. At first, these unrelated events gradually acquire common features. The trail leads detectives to a young woman, Stasya, who, for the sake of her child, decides to kill her close friend.
An attempt was made on businessman Marat Shaikenov. Shaikenov believes that this is the same sniper who has been keeping the entire city in fear for a month, committing more and more murders. Shaikenov turns to the Beagle detective agency with a request to find the sniper. Moreover, death now threatens not only him, but also his fiancée Ella. Investigating this complicated case, private detective Andrei Rostovtsev meets family psychologist Alina Belova, who, thanks to her professional experience, helps Rostovtsev identify the criminal. Rostovtsev invites Alina to become a member of his team.
Alina's fiancé, the famous journalist Dmitry Aristov, lost a flash drive with compromising information on Deputy Governor Stanislav Kravchenko, who, according to his wife Maryana, was involved in the murder of their housekeeper. The detectives, along with a new member of the team, 18-year-old Young, get down to business. One version replaces another, mysteries multiply. Thanks to Alina's professional instincts, she manages to figure out the true killer, whose name comes as a surprise to the whole team. After the successful completion of the case, Alina accepts Andrei Rostovtsev’s offer to become a full-time psychologist at the Beagle detective agency.