The book documents Ginzburg's discovery of a "fertility cult among the peasants of early modern Friuli,
who believed that those who were marked out by being born with the caul formed an elite whose souls at intervals
left their bodies to fight maleficent witches to protect their village's crops from harm. The battle was waged
by the benandanti with sticks of fennel and by the witches with sorgum, and if the benandanti won the success of
the harvest was assured, whereas if the witches did it was blighted. These beliefs came to light through the investigations
of the Inquisition, whose . . . records on the topic (a sample of which is included as an appendix) form the basis
of the book."(History)