Daniela is a quiet single mother studying for a doctorate in chemistry. She rarely goes out, so her murder in her bedroom at the family's new villa seems inexplicable. It is true that her mother, who appears to be an alcoholic; her younger sister, who has had mental problems; and her father, who has made his money running nightclubs and is probably involved in the international sex trade, are not your average home-loving Italian nuclear family, but what can she have done to be singled out for slaughter? And why has the prosecutor asked specifically for Marshal Guarnaccia to head the investigation?