In the world of family Italian restaurants, old grudges from the village are stirred up when matriarch Nonna Luisa dies and the ownership of a secret book of recipes becomes the suspected motive.

When Phryne's Aunt Prudence opens her home to psychiatrist and natural healer, Hayden Samuels, to conduct his sanatorium for 'hysterical' women, Phryne takes on more than she bargained for.