A tragedy of a young "senior of the Vistula river rascals". Rysiek Cwaniak accidentally meets a Lady in a city tavern, who, delighted with Cwaniak's dance with her Black Staszka, kidnaps him into a dance whirl. The Lady's eyes strangely hypnotize the young Crafty and for a long time they do not let him forget about this alluring and mysterious Lady, but she, Baron Ilsky's mistress, does not even think about the accidental acquaintance and does not suppose that a momentary joke could shatter the current life of the bunch of people.