King Matthias gets tired of the usual domestic tiffs, so he leaves the capital and travels through the country in disguise. His jealous wife also puts on a disguise and follows her husband to find out what he is doing.
Diversants are being prepared to destroy the military factory. Géza Torday comes as a new engineer and his appearance deeply disturbs the situation, as Toth, the director of the factory, sells goods to the West.