There are a number of inheritors to a fortune who are getting killed by a mysterious somebody whom we do not see. Each death is novel, but not terribly graphic. Who did it?

Ricciardetto is a fourteenth-century playboy who wants at all costs to sleep with the wife of the mayor of Montelupone. He succeeds, but is caught between the covers with the woman and sentenced to death. He will be saved by a kind of pilgrim saint who is in love with him.