Painting Mona Lisa. Jeanne Kalogridis

weather had turned bitterly cold; Baroncelli’s final breaths hung before him as mist. The top of his cloak gaped open, but he could not pull it closed, for his hands were bound behind his back.

      In this manner, unsteady and lurching each time the wheels encountered a stone, Baroncelli arrived in the Piazza. No fewer than a thousand had gathered to witness his end.

      At the crowd’s edge, a small boy, a fanciulo, caught sight of the approaching cart and, in his childish falsetto, sang out the rallying cry of the Medici: ‘Palle! Palle! Palle!’

      Hysteria rippled through the throng. Soon its collective shout thundered in Baroncelli’s ears.

      ‘Palle! Palle! Palle!’

      Someone nearby threw a stone; it clattered harmlessly against the cobblestones beside the creaking cart. Only curses were hurled afterwards. The Signoria had placed several policemen on horseback at strategic locations to prevent a riot; Baroncelli was flanked by mounted, armed guards.

      This was to prevent him from being torn apart before he could be properly executed. He had heard the tales of his fellow conspirators’ gruesome fates: how the Perugian mercenaries hired by the Pazzi had been pushed from the high tower of the Palazzo della Signoria, how they had fallen into the waiting crowd below, who had hacked them to pieces with knives and shovels.

      Even old Iacopo de’ Pazzi, who during his life had been respected, had not escaped Florence’s wrath. Upon the sound of Giotto’s chiming campanile, he had climbed upon his horse and tried to rally the citizens with the cry, Popolo e liberta! The phrase was a rallying cry to overthrow the current government – in this case, the Medici.

      But the populace had answered with the cry: Palle! Palle! Palle!

      Despite his sin, he had been granted a proper burial after his execution – with the noose still round his neck. But the city had been so filled with hatred in those wild days, he had not been at rest long before his cadaver was dragged through the streets and reburied outside the city walls, in unhallowed ground.

      Francesco de’ Pazzi and the rest had swiftly met justice; only Guglielmo de’ Pazzi had been spared, because of Bianca de’ Medici’s desperate pleading with her brother Lorenzo.

      Of the true conspirators, Baroncelli alone had escaped – by hiding in the Duomo’s campanile, its air still aquiver from the ringing of the bell. When his way was clear, he had fled on horseback – without a word to his family – due east, to Senigallia on the coast. From there, he had sailed to exotic Constantinople. King Ferrante and Baroncelli’s Neapolitan relatives had sent funds enough to sustain a dissolute life. Baroncelli made mistresses of the slave girls he had purchased, immersing himself in pleasure and trying to submerge all memory of the murders he had committed.

      Yet his dreams were haunted by the image of Giuliano, frozen at the instant he had glanced up at the shining blade. The young man’s dark curls were tousled, his innocent eyes wide, his expression unselfconscious and slightly dazed by the sudden appearance of Death.

      Baroncelli had had more than a year to contemplate the question: Would removing the Medici and replacing them with Iacopo and Francesco de’ Pazzi have bettered the city? Lorenzo was level-headed, cautious; Francesco hot-tempered, swift to act. He would quickly have descended to the level of a tyrant. Lorenzo was wise enough to nurture the people’s love, as evidenced by the size of the crowd now gathered in the plaza; Francesco would have been too arrogant to care.

      Lorenzo was, most of all, persistent. In the end, even Constantinople was not beyond his reach. Once his agents had located Baroncelli, Lorenzo had sent an emissary laden with gold and jewels to the Sultan. Thus was Baroncelli’s fate sealed.

      All criminals were hanged outside the city gates, then hastily stuffed into unhallowed ground. Baroncelli would be buried in a hole with them – but given the gravity of his misdeed, his execution was to take place in Florence’s most public arena.

      Now, as the little cart rattled past the crowd towards the scaffolding, Baroncelli let go a loud groan. Fear gripped him with an anguish far worse than any physical pain; he felt unbearably cold, searingly hot, felt a dizzying sense of sinking. He thought he would faint, yet unconsciousness, cruelly, would not come.

      ‘Courage, Signore,’ the nero said. ‘God rides with you.’

      His nero, his Comforter, walked alongside the cart. He was a Florentine citizen named Lauro, and a member of the Compagnia di Santa Maria della Croce, also known as the Compagnia de’ Neri – the Company of the Black Ones – because its members all wore long black robes and hoods. The Company’s purpose was to give comfort and mercy to all those in need – including those anguished souls condemned to die.

      Lauro had remained with him from the moment he had arrived in Florence. He had seen to it that Baroncelli received fair treatment, was allowed proper clothing and food, that he was permitted to send letters to loved ones (Giovanna never responded to his plea to see her). Lauro had listened kindly to Baroncelli’s tearful admissions of regret, and remained in the cell to pray for him. The Comforter had beseeched the Virgin, Christ, God and Saint John, patron of Florence, to give Baroncelli comfort, to grant him forgiveness, to allow his soul into Purgatory and thence to Heaven.

      Baroncelli did not join him in prayer; God, he felt, would take it as a personal affront.

      Now, the black-hooded Comforter walked beside him, speaking loudly – a psalm, a hymn, or prayer, all floating on the air as white vapour – but given the noise made by the crowd, Baroncelli could not make out the words. A single phrase thrummed in his ears and pulsed to the beating of his heart.

       Palle Palle Palle

      The cart rolled to a stop in front of the steps leading up to the gallows. The Comforter slid an arm under Baroncelli’s bound one and helped him awkwardly onto the cold flagstone. The weight of terror dropped the shivering Baroncelli to his knees; the Comforter knelt beside him and whispered in his ear.

      ‘Do not be afraid. Your soul will ascend directly to Heaven. Of all men, you need no forgiveness; what you did was God’s own work, and no crime. There are many of us who call you hero, brother. You have taken the first step in purging Florence from great evil.’

      Baroncelli’s voice shook so he could scarce understand his own words. ‘From Lorenzo?’

      ‘From debauchery. From paganism. From the pursuit of profane art.’

      Teeth chattering, Baroncelli glared at him. ‘If you – if others – believe this, then why have you not rescued me before now? Save me!’

      ‘We dare not make ourselves known. There is much to be done before Florence, before Italy, before the world is ready for us.’

      ‘You are mad,’ Baroncelli breathed.

      The Comforter smiled. ‘We are fools for God.’

      He helped Baroncelli to his feet; enraged, Baroncelli pulled away from him, and staggered up the wooden steps alone.

      On the scaffold, the executioner, a slender man whose face was hidden beneath a mask, stood between Baroncelli and the waiting noose. ‘Before God,’ the executioner said to Baroncelli, ‘I beg your forgiveness for the act I am sworn to commit.’

      The inside of Baroncelli’s lips and cheeks cleaved to his teeth; his tongue was so dry, it left behind a layer of skin as he articulated the words. Yet his tone sounded astonishingly calm. ‘I forgive you.’

      The executioner released a small sound of relief; perhaps there had been other doomed men more eager to let their blood stain his hands. He caught Baroncelli’s elbow and guided him to a particular spot on the platform, near the noose. ‘Here.’ His voice was oddly gentle. And he produced from within his cloak a white linen scarf.

      In the instant before he was blindfolded, Baroncelli scanned the crowd. Near the front was Giovanna, with the children. She was too distant for Baroncelli to be sure, but it seemed to him that she had been weeping.

      Lorenzo