The discovered drawings of the painter Jan Zrzavý will not bring happiness to their heiress and participant in the art course run by Ctirad Karafiát. She is found murdered in her house, from where the master's drawings also disappeared. Is the perpetrator one of the members of the art course, or one of the relatives of the murdered? The monastery's detectives, led by Captain Petr Beránek, have to unravel another complicated case. In parallel with them, Ctirad Karafiát is conducting his own investigation, just like in previous cases, and he is not doing badly at all.