On the eve of the Soviet-Finnish war, enemy intelligence is intensifying. Finnish intelligence sends its most valuable agent to Leningrad, previously “mothballed” and saved for emergencies. He was given a task of special importance - such importance that he was allowed to use all the reserves of the Finnish residency and was allowed to resort to any, even the most radical methods, in other words, stop at nothing. State Security Captain Shepelev and his task force will have to identify the spy and detain him.