Острог. Дело Федора Сеченова

The head of the pre-trial detention center was killed. Fyodor Sechenov is assigned to investigate the crime. Trying to understand who could have killed his friend, the investigator is faced with negativity from employees and prisoners. At the same time, a valuable archive disappears from prison. Gradually, Fedor realizes that a real person is involved in the mysterious events, who has subjugated the entire detention center. Will he be able to find the puppet master before the next murder occurs?