Först när givaren är död

In the middle of the Medieval fair in Visby the house of a 70-year-old woman is set on fire, and she is presumed dead. When another murder occurs Maria Wern and her police colleagues head for a picturesque summer town where everybody knows each other - and where the discovery of several Latin texts and incomprehensible drawings makes the police suspect that all the events have something to do with the medieval fair.