Lieutenant Colonel Medvedev has been working in the police for the last few days. Firstly, the RUBOP, in which Nikolai gave twenty years of his life to serve, was decided to be disbanded, and secondly, Medvedev, succumbing to the insistence of his wife, was going to retire from the police force based on his years of service. On the eve of his dismissal, the operative has to participate in an operation to apprehend a dangerous criminal - a famous killer nicknamed Harness.
Realizing that this seasoned criminal will effortlessly bypass the ambush, Medvedev decides to detain him on his own, and he succeeds. This incident decisively changes his fate. Nikolai is summoned by his boss, General Kireev, and offers to head the new experimental department. Medvedev and his employees will have to protect witnesses whose lives and health are being threatened in connection with the investigation of certain criminal cases.