‘Do you want to put that down and rest for a moment, Ezio?’ Leonardo asked. ‘It might be a bit too heavy for you.’

Ezio gritted his teeth. ‘No, grazie. Anyway, we’re almost there.’

When they arrived at the Palazzo Auditore, he carried his box into the entrance hall and set it down as slowly and as carefully as his aching muscles would let him, and he was more relieved than he’d ever admit, even to himself.

‘Thank you, Ezio,’ said his mother. ‘I think we can manage very well without you now, though of course if you wish to come and help with the hanging of the pictures -‘

‘Thank you, Mother – I think that’s a job best left to the two of you.’

Leonardo held out his hand. ‘It was very good to meet you, Ezio. I hope our paths cross again soon.’

‘Anch’io.’

‘You might just call one of the servants to give Leonardo a hand,’ Maria told him.

‘No,’ said Leonardo. ‘I prefer to take care of this myself. Imagine if someone dropped one of the boxes!’ And bending his knees, he hoisted the box Ezio had put down into the crook of his arm. ‘Shall we?’ he said to Maria.

‘This way,’ said Maria. “Goodbye, Ezio, I’ll see you at dinner this evening. Come, Leonardo.’

Ezio watched as they left the hall. This Leonardo was obviously one to respect.

After lunch, late in the afternoon, Giulio came hurrying (as he always did) to tell him that his father required his presence in the office. Ezio hastened to follow the secretary down the long oak-lined corridor that led to the back of the mansion.

‘Ah, Ezio! Come in, my boy.’ Giovanni’s tone was serious and businesslike. He stood up behind his desk, on which two bulky letters lay, wrapped in vellum and sealed.

‘They say Duke Lorenzo will return tomorrow or the day after at the latest,’ said Ezio.

‘I know. But there is no time to waste. I want you to deliver these to certain associates of mine, here in the city.’ He pushed the letters across the desk.

‘Yes, Father.’

‘I also need you to retrieve a message which a carrier pigeon should have brought to the coop in the piazza at the end of the street. Try to make sure no one sees you fetch it.’

‘I’ll see to it.’

‘Good. Come back here immediately you’ve finished. I have some important things I need to discuss with you.’

‘Sir.’

‘So, this time, behave. No scrapping this time.’

Ezio decided to tackle the pigeon coop first. Dusk was approaching, and he knew there’d be few people out at that time – a little later the square would be thronged with Florentines making their passeggiata. When he reached his goal he noticed some graffiti on the wall behind and above the coop. He was puzzled: was it recent or had he just never been aware of it before? Carefully inscribed was a line he recognized from the Book of Ecclesiastes: HE THAT INCREASETH KNOWLEDGE INCREASETH SORROW. A little below this, someone had added in a ruder script: WHERE IS THE PROPHET?

But his mind soon returned to his task. He recognized the pigeon he was after instantly – it was the only one with a note attached to its leg. He detached it quickly and gently placed the bird back on its ledge, then he hesitated. Should he read the note? It wasn’t sealed. Quickly he unrolled the little scroll and found it contained nothing but a name – that of Francesco de’ Pazzi. Ezio shrugged. He supposed that would mean something more to his father than it did to him. Why the name of Vieri’s father and one of the possible conspirators in a plot to topple the Duke of Milan – facts already known to Giovanni – should be of further significance was beyond him. Unless it signified some kind of confirmation.

But he had to hurry on with his work. Stashing the note in his belt-pouch, he made his way to the address on the first envelope. Its location surprised him, for it was in the red-light district. He’d been there often with Federico – before he had met Cristina, that is – but he had never felt comfortable there. He placed a hand on his dagger-hilt to reassure himself as he approached the dingy alley his father had indicated. The address turned out to be a low tavern, ill-lit and serving cheap Chianti in clay beakers.

At a loss about what to do next, for there seemed to be no one about, he was surprised by a voice at his side.

‘You Giovanni’s boy?’

He turned to confront a rough-looking man whose breath smelled of onions. He was accompanied by a woman who might once have been pretty, but it looked as if ten years on her back had rubbed most of any loveliness away. If it was left anywhere, it was in her clear, intelligent eyes.

‘No, you idiot,’ she said to the man. ‘He just happens to look exactly like his dad.’

‘You got something for us,’ said the man, ignoring her. ‘Give it here.’

Ezio hesitated. He checked the address. It was the right one.

‘Hand it over, friend,’ said the man, leaning closer. Ezio got a full blast of his breath. Did the man live on onions and garlic?

He placed the letter in the man’s open hand, which closed round it immediately and transferred it to a leather pouch at his side.

‘Good boy,’ he said, and then smiled. Ezio was surprised to see that the smile gave his face a certain – surprising – nobility. But not his words. ‘And don’t worry,’ he added. ‘We ain’t contagious.’ He paused to glance at the woman. ‘At least, I ain’t!’

The woman laughed and punched his arm. Then they were gone.

Ezio made his way out of the alley with relief. The address on the second letter directed him to a street just west of the Baptistry. A much better district, but a quiet one at this time of day. He hastened across town.

Waiting for him under an arch which spanned the street was a burly man who looked like a soldier. He was dressed in what looked like leather country clothes, but he smelled clean and fresh, and he was cleanshaven.

‘Over here,’ he beckoned.

‘I have something for you,’ said Ezio. ‘From -‘

‘- Giovanni Auditore?’ The man spoke little above a whisper.

‘Sì.’

The man glanced around, up and down the street. Only a lamplighter was visible, some distance away. ‘Were you followed?’

‘No – why should I have been?’

‘Never mind. Give me the letter. Quickly.’

Ezio handed it over.

‘Things are hotting up,’ said the man. ‘Tell your father they’re making a move tonight. He should make plans to get to safety.’