In 1st century Rome, public gardens created by Julius Caesar have become dangerous haunts, especially for women alone. When her husband has to leave the city, Flavia Albia is left to supervise his building project in an old grotto. Soon it becomes apparent that a dangerous serial killer has made the Grove his killing ground. In this edition of Historical Fiction, Alice Roberts talks to Lindsey Davis, the unassailable market leader in the "crime in Ancient Rome" genre.