The series is set in the 1920s. It tells about the first tasks of Isaev. First, he goes to Reval to stop the smuggling of valuables stolen from Gokhran. Upon his return, he is sent to Vladivostok to collect information about the actions of the whites. Then he has to go abroad to monitor counterrevolutionary emigration.
A young girl Kseniya becomes a nurse in the Russian Army during the WWI.
