The naked body of a young woman is discovered on a beach near Vigata. The girl was shot in the face, her identity is unknown and the only clue police have to go on is a butterfly tattoo on her shoulder. Montalbano sets to work trying to establish the girl's identity and investigates possible links between the murder victim and a local charity with connections to the church. Meanwhile, his relationship with Livia continues to suffer as a result of his poor work/life balance.