Today is the release day for Jo Graham’s marvelous The Blood of the Bull, the third in her Memoirs of the Borgia Sibyl, which recounts the magical life of Giulia Farnese, mistress of the notorious Borgia pope Alexander VI. In Jo’s telling, Giulia is more than merely a formidably learned advisor and patroness: she is a seer, a Dove, developing her power through the dangerous new scholarship flourishing in the Renaissance. In A Blackened Mirror and The Borgia Dove, she took her place at Rodrigo Borgia’s side, first to defeat plots against the then-cardinal’s life, and then to work with his family and allies to see him elevated to the papacy. She has chosen, in the classical language of her era, to be Persephone to the Borgia Hades, and as such — as his acknowledged mistress — she has risen to the heights of power and influence.

But now a French army is marching toward the Kingdom of Naples, and Rodrigo’s enemies would be glad to see him deposed, even if that means that the French sack the city of Rome and kill thousands in the process. The Papal States’ power doesn’t lie in arms, and the French wield dozens of new-fangled cannon, easily enough to bring down the city walls.

And in Florence, an even darker threat is growing. Friar Savonarola is determined to purify society, and is burning books and priceless works of art, eager to destroy the Renaissance itself. Giulia is the perfect target for his purifying zeal: the repentant concubine of the corrupt Borgia would be the perfect tool to bring Alexander VI to his knees.

Tangled in a web of deceit, assassination, and betrayal, Giulia must face her most dangerous enemies without Rodrigo at her side. She will need all her wits and courage to descend into the darkness of the underworld — and return if she can.

Graham captures the period magnificently: a world at once earthy and devout, steeped in classical learning and medieval theology, magic and cutthroat politics, the street-fighters’ swords and the condottiere’s cannon. As always, her grasp of historical detail is impeccable, and the story-telling is mesmerizing. My heart was in my throat as the noose tightened on the city. Giulia’s voice is pitch perfect, capturing Renaissance Rome in all its terrifying, glorious complexity. It’s out today, available here and on most platforms.