The trail of London's Jack the Ripper leads Sherlock Holmes to St. Petersburg. Here, the murders continue, and Dr. Kartsev and the beautiful stranger Sophia take on helping the English detective.
Dr. Kartsev rescues a wounded Netochka at night, but the Ripper manages to finish what he started. The bloody killer is still one step ahead, and Holmes himself is among the suspects.
Sherlock is about to return to London, but a student Anton Sviridov stops him on the threshold and informs him about the murder of his family. The maid was missing, the windows and doors were locked from the inside, and the mother and brother were frozen in a smile. Difficult concludes that they were victims of a vampire. Anton thinks Difficult is crazy, and his only hope of finding out the truth is Sherlock.
Another murder was committed with a similar handwriting. The Chief of police considers Anton Sviridov guilty, he is sent to prison. According to Holmes, the riddles of Sviridov's father's past are to blame for everything.
Sophia turns to Holmes. Her friend, actress Alla Insarova, was killed. She threw herself off the roof, there are no signs of violence, and, according to the police, this is suicide. But Sofia is sure that Alla could not do that, because she was young, successful and in love.
Sherlock finds out that the murdered actress Alla had a lover. The only clue in the investigation is exclusive cigarettes, and the trail of this evidence leads to the imperial court.
Before leaving for London, Sherlock takes up a case that seems to him a nice trifle - the laundress Agafya complains that someone is dirtying her laundry while it is drying on the roof. Holmes and Dr. Kartsev arrange an ambush, and suddenly a trifle turns into a matter of national importance.
Ritual murders continue, the victims are linked by age, social status and boutonniere. However, Sherlock is suspended from business, nothing holds him in Russia anymore, and he offers Sophia to run away together.
