He paused again, breathing hard. Now for the tower. This was of more smoothly trimmed stone, and the going was hard. What’s more, he had to climb round from the north to the west side of it, where the cell window was. He prayed that no one in the square or on the battlements would look up. He didn’t fancy being brought down by a crossbow bolt after having got so far.

The corner where the north and west walls met was hard and unpromising, and for a moment Ezio clung there, frozen, looking for a handhold that didn’t seem to exist. He looked down, and saw far beneath him one of the guards on the battlements looking up. He could see the pale face clearly. He could see the man’s eyes. He pressed himself to the wall. In his dark clothing he’d be as conspicuous as a cockroach on a white tablecloth. But, inexplicably, the man lowered his gaze and continued his patrol. Had he seen him? Had he not been able to believe what he’d seen? Ezio’s throat thumped with the strain. Only able to relax after a long minute had passed, he breathed once more.

After a monumental effort he arrived at his goal, grateful for the narrow ledge on which he could just perch as he peered into the narrow cell beyond the window. God is merciful, he thought, as he recognized the figure of his father, his back turned towards him, apparently reading by the thin light of a taper.

‘Father!’ he called softly.

Giovanni spun round. ‘Ezio! In God’s name, how did you -‘

‘Never mind, Father.’ As Giovanni approached, Ezio could see that his hands were bloody and bruised, and his face pale and drawn. ‘My God, Father, what have they done to you?’

‘I took a bit of a beating, but I’m all right. More importantly, what of your mother and sister?’

‘Safe now.’

‘With Annetta?’

‘Yes.’

‘God be praised.’

‘What happened, Father? Were you expecting this?’

‘Not as quickly as this. They arrested Federico and Petruccio too – I think they’re in the cell behind this one. If Lorenzo had been here things would have been different. I should have taken precautions.’

‘What are you talking about?’

‘There’s no time for that now!’ Giovanni almost shouted. ‘Now, listen to me: you must get back to our house. There’s a hidden door in my office. There’s a chest concealed in a chamber beyond it. Take everything you find inside it. Do you hear? Everything! Much of it will seem strange to you, but all of it is important.’

‘Yes, Father.’ Ezio shifted his weight slightly, still clinging for dear life to the bars that crossed the window. He didn’t dare look down now, and he didn’t know how much longer he could remain motionless.

‘Among the contents you’ll find a letter and with it some documents. You must take them without delay – tonight! – to Messer Alberti -‘

‘The Gonfalionere?’

‘Exactly. Now, go!’

‘But, Father…’ Ezio struggled to get the words out, and, wishing that he could do more than just ferry documents, he stammered, ‘Are the Pazzi behind this? I read the note from the carrier pigeon. It said -‘

But then Giovanni hushed him. Ezio could hear the key turning in the lock of the cell door.

‘They’re taking me for interrogation,’ said Giovanni grimly. ‘Get away before they discover you. My God, you’re a brave boy. You’ll be worthy of your destiny. Now, for the last time – go!’

Ezio edged himself off the ledge and clung to the wall out of sight as he heard his father being led away. He almost couldn’t bear to listen. Then he steeled himself for the climb down. He knew that descents are almost always harder than ascents, but even in the last forty-eight hours he’d gained plenty of experience of scaling up and down buildings. And now he clambered down the tower, slipping once or twice, but regaining his hold, until he had reached the battlements again, where the two guardsmen still lay where he had left them. Another stroke of luck! He’d knocked their heads together as hard as he could, but if they’d chanced to regain consciousness while he was up on the tower and raised the alarm… well, the consequences didn’t bear thinking about.

Indeed, there was no time to think of such things. He swung himself over the battlements and peered down. Time was of the essence. If he could see something down below which might break his fall, he might dare to leap. As his eyes adjusted to the gloom, he saw the awning of a deserted stall attached to the wall, far below. Should he risk it? If he succeeded, he’d gain a few precious minutes. If he failed, a broken leg would be the least of his problems. He would have to have faith in himself.

He took a deep breath and dived into the darkness.

From such a height the awning collapsed under his weight, but it had been firmly secured and gave just enough resistance to break his fall. He was winded, and he’d have a few bruised ribs in the morning, but he was down! And no alarm had been raised.

He shook himself and sped off in the direction of what only hours ago had been his home. When he reached it, he realized that in his haste his father had neglected to tell him how to locate the secret door. Giulio would know, but where was Giulio now?

Luckily there had been no guards lurking in the vicinity of the house, and he’d been able to gain access unchallenged. He had stopped for a minute, outside the house, almost unable to propel himself in through the darkness of the doorway – it seemed that the house had changed, its sanctity defiled. Again, Ezio had to collect his thoughts, knowing that his actions were critical. His family depended on him now. He pressed on into his family home, into the dark. Shortly afterwards he stood in the centre of the office, eerily lit by a single candle, and looked about him.

The place had been turned over by the guards, who had clearly confiscated a large number of bank documents, and the general chaos of fallen bookcases, overturned chairs, drawers cast to the ground and scattered papers and books everywhere didn’t make Ezio’s task any easier. But he knew the office, his eyesight was keen, and he used his wits. The walls were thick, any could have a chamber concealed within them, but he made for the wall into which the large fireplace was set and started his search there, where the walls would be thickest, to contain the chimneypiece. Holding the candle close, and looking searchingly, while keeping an ear cocked for any sound of returning guards, finally, on the left-hand side of the great moulded mantel he thought he could discern the faint outline of a door set into the panelling. There had to be a means of opening it nearby. He looked carefully at the carved colossi which held the marble mantelpiece on their shoulders. The nose of the one on the left-hand side looked as if it had once been broken, and repaired, for there was a fine crack around its base. He touched the nose and found it to be slightly loose. Heart in mouth, he moved it gently, and the door swung inwards on silent spring-mounted hinges, revealing a stone-floored corridor which led to the left.