In the second film of the medieval thriller, the night watchman is frightened by a terrible ghost — the tragically drowned daughter of a rich merchant. By morning, the guard has fallen to his death from a high tower, and several more people lose their lives in suspicious accidents.

Investigating these events, Melchior's path crosses with a prostitute, a priest, a foreign artist, and a mad heretic. The clues lead him to the Pirita Convent, whose gloomy vaults hide a dangerous secret buried in oblivion.

At the same time, Melchior is troubled by the question of why his beloved Keterlyn suddenly breaks their engagement.