Plot
Saint Petersburg police major Igor Grom is chasing three bank robbers dressed in red sports suits and disguised as villainous hockey players from the popular Soviet cartoon Puck! Puck! He catches them, while causing significant property damage, and gets reprimanded by his superior, Colonel General Fedor Prokopenko.
Soon after, the trial of "rich boy" Kirill Grechkin begins; he is accused of fatally hitting a girl with his car. Despite the evidence against him, Grechkin is acquitted and the brother of the deceased, Lyosha Makarov, suspects the court of corruption. IT millionaire Sergei Razumovsky, founder of the social network Vmeste, and his friend Oleg Volkov, who grew up in the same orphanage as the deceased girl, are also outraged by the court's decision. At the same time, videos of the Plague Doctor appear on the internet—an avenger in a mask and a combat suit, armed with bombs and flamethrowers, who promises to "cleanse" the city of scoundrels. The Doctor burns Kirill Grechkin to death in his car. After the murder, Oleg comes to Razumovsky and confesses that he was the Doctor. Razumovsky is upset by this, but hesitates to turn his friend in to the authorities.
Grom, who witnessed the murder, is trying to investigate it and find the Doctor, who is now considered by many to be a hero. FSB officer Evgeny Strelkov, who arrives from Moscow to capture the Doctor, removes the major from the case. Instead, Grom and his new trainee, Dima Dubin, are sent to deal with the theft of twelve refrigerators. However, contrary to their official assignment, the two continue to investigate the Doctor's case, having received a tip from Grom's informant and unsuccessfully trying to knock information out of people associated with the criminal underworld. In the meantime, Grom saves a young woman from thugs, but she turns out to be journalist and blogger Yulia Pchyolkina, who staged the attack in order to get close to Grom and obtain information about the Plague Doctor case for her blog.
Meanwhile, the Doctor accumulates new victims: the head of a bank that defrauded depositors and the owner of a polluting landfill, along with the latter's entire family. Dubin speculates that the Doctor's next appearance will be at the opening of a casino, where the crème de la crème of St. Petersburg society will gather. Grom infiltrates the opening party, where he meets Pchyolkina and Razumovsky. Instead of the real Doctor, however, only his followers appear, wanting to rob the rich. Sergei Razumovsky tries to prevent the violence and dissuade them with money, but a fight ensues, in which Grom and a number of FSB officers capture the bandits. Grom is subsequently forced to resign from the police by Strelkov.
Despite his dismissal, he continues his investigation and learns about Razumovsky's childhood in the orphanage, and that he used to draw birds that looked like the Doctor's mask. Back at the casino, Pchyolkina had told Grom about Razumovsky's contract with Holt International, a company engaged in high-tech weapons development. It was Holt International that created the Plague Doctor's costume and equipment. Grom directly accuses Razumovsky of being the Plague Doctor. By this point, Sergei has realized that the accusation is true: "Oleg" was his secondary personality (Grom points out that according to official documents, the real Oleg Volkov died in the war in Syria a year before). His dark side takes over; he knocks Grom out with a blow to the head, puts the Doctor's suit on him, and tosses him near the site of his next murder. The police grab Grom, and Strelkov now believes that Igor is the Doctor.
Dubin and Pchyolkina help Grom escape from custody, and he goes on the hunt for the Doctor. Meanwhile, the vigilante publishes a new video: he calls on all his followers to fill the streets and lynch anyone they consider to be a villain. Spontaneous pogroms begin in the city. Razumovsky confesses to Igor that in this way, he wants to get rid of not only corrupt officials and rich people, but also his followers, whom he considers to be immoral imitators and misfits; in his opinion, the state will be forced to send troops and kill them, and Razumovsky will subsequently be able to create a "new Petersburg". A fight breaks out between Grom and Razumovsky, in which the Doctor almost wins, but Dubin and Pchyolkina come to Grom's rescue. Razumovsky is neutralized, and Pchyolkina reveals that she recorded his boasting speech, including his nefarious plans. Grom declares to the Doctor that he also sees problems in the country, but considers it unacceptable to solve them by means of murder.
Meanwhile, the pogroms quickly subside when a gang led by one of Grom's informants acts against the rioters. Lyosha Makarov, who participated in them, is planning to kill the corrupt judge who released Grechkin. When his grandchildren visit him, however, Lyosha realizes that he is incapable of committing the murder, and spares him. FSB officer Strelkov claims all credit for the apprehension of the Plague Doctor, while Grom is content to spend time with his new friends, Dubin and Pchyolkina.
In a mid-credits scene, Razumovsky is shown in a mental institution. His "dark side" speaks to him, telling him that "they" will soon be free. In a post-credits scene, Oleg Volkov is shown in a militant camp in Syria: it turns out that he is still alive, and he watches his friend Razumovsky's capture on television.
