Caterina Gonzaga gave a faint moan as the long blade went in and out again, unhurried as a serpent’s tongue. Sandro tried to block my eyes, but too late. I saw the droplets of blood like a trail of rubies trickling from Perotto’s doublet. I could hear one of the women behind me begin babbling a prayer, hear Perotto’s small, astonished mew like a dying cat, but I couldn’t take my eyes from that trail of red drops. I followed it back to Leonello, bare-headed and scarlet-handed in the door. Not really scarlet-handed, I suppose. His hands looked quite clean as he sheathed the knife at his waist. But his nimble, double-jointed fingers looked red to me, red, red, red. He glanced up and for a moment I met his eyes.

“A private matter, Your Holiness.” Cesare sheathed his sword calmly, giving a nod to the papal guards. “A family matter. No need to concern yourself. Take him,” he added, and two stone-faced guards seized a limp, gasping Perotto under his arms. He opened his mouth as though to scream as they hauled him up, but only a trickle of a moan came out, like the trickle of blood from the fists he’d clamped over his stomach. Not a very large wound, really, to turn a vigorous young man into this broken puppet.

“No need to concern yourself, Your Holiness,” Cesare repeated as Perotto was dragged out. Rodrigo gave a nod; he no longer looked so gray about the mouth.

“Not so publicly next time, Cardinal Borgia,” he chided, and held his cup out. A wide-eyed page boy had to be nudged twice before he scurried forward to pour the Holy Father’s wine.

Cesare’s eyes found Leonello, still standing quiet in the doorway with his boots apart. “You heard him, little lion man. More discretion in future.”

Leonello bowed. “Apologies,” he said again, and when he turned I saw the frisson of horror that rippled through the crowd of guests, how they flinched away from even looking him in the eye. They flinched like that for Michelotto, Cesare’s human sword with the dead gaze. For Cesare himself.

I wasn’t aware I was following Leonello until Sandro seized my arm. “No, sorellina,” he hissed. I jerked my arm away, but Leonello was already gone. There was half a bloody boot print on the marble where he’d stood, and as Cesare curtly ordered the guests out I saw how superstitiously they skirted it. As though lightning would strike them if they trod on that bloody print.

“Giulia,” the Holy Father called as Orsino took my arm and tried to lead me out. “Stay with Us a moment.”