Major Andrey Frolov returned to the Criminal Investigation Department of St. Petersburg and rose to the rank of senior officer. Together with Venya Solntsev, he is preparing an operation to apprehend a gang of counterfeiters, but it is disrupted by the plumber Grishin from the Red Hammer. Andrey still manages to detain the leader of the criminal group, but the very next day he is released due to lack of evidence. In this regard, the management again sends Frolov to the Red Hammer.