Uprooted from her ancestral home of Aquilac in the South of France, Francesca Allegri comes to live with her uncle, the noted composer Gregorio Allegri, in Rome. Almost instantly, this highly educated, headstrong woman is plunged into the high-stakes intrigues of the Vatican. Her defiance of a papal decree makes her an enemy of the establishment who chase her and her lover all across Europe. If she is caught, a dungeon awaits and, perhaps, burning at the stake. Her response? She stokes their anger even further by authoring a book, more heretical even than Galileo, in which she challenges the Church's worldview.