‘You remember the first one?’ asked Ezio.

‘How could I forget?’ The artist gazed at the page. ‘This is most exciting! May I?’

‘Of course.’

Leonardo studied the page carefully, running his fingers over the parchment. Then, drawing paper and pens towards him, he began to copy the words and symbols down. Almost immediately, he was darting to and fro, consulting books and manuscripts, absorbed. Ezio watched him work with gratitude and patience.

‘This is interesting,’ said Leonardo. ‘Some quite unknown languages here, at least to me, but they do yield a kind of pattern. Hmmn. Yes, there’s a gloss here in Aramaic which makes things a bit clearer.’ He looked up. ‘You know, taking this with the other page, you’d almost think they were part of a guide – on one level, at least – a guide to various forms of assassination. But of course there’s far more to it than that, though I have no idea what. I just know that we’re only scratching the surface of what this may have to reveal. We’d need to have the whole thing complete, but you’ve no idea where the other pages are?’

‘None.’

‘Or how many in the complete volume?’

‘It is possible that… that that may be known.’

‘Aha,’ said Leonardo. ‘Secrets! Well, I must respect them.’ But then his attention was caught by something else. ‘But look at this!’

Ezio looked over his shoulder but could see nothing but a succession of closely grouped, wedge-shaped symbols. ‘What is it?’

‘I can’t quite make it out, but if I’m right this section contains a formula for a metal or an alloy that we know nothing of – and that, logically, shouldn’t possibly exist!’

‘Is there anything else?’

‘Yes – the easiest bit to decipher. It’s basically the blueprint for another weapon, and it seems to complement the one you already have. But this one we’ll have to make from scratch.’

‘What kind of weapon?’

‘Fairly simple, really. It’s a metal plate encased in a leather bracer. You’d wear it on your left forearm – or your right if you were left-handed, like me – and use it to ward off blows from swords or even axes. The extraordinary thing is that although it’s evidently very strong, the metal we’re going to have to cast is also incredibly light. And it incorporates a double-bladed dagger, spring-loaded like the first.’

‘Do you think you can make it?’

‘Yes, though it will take a little time.’

‘I haven’t much of that.’

Leonardo pondered. ‘I think I have all I need here, and my men are skilled enough to forge this.’ He thought for a moment, his lips moving as he made calculations. ‘It will take two days,’ he decided. ‘Come back then and we’ll see if it works!’

Ezio bowed. ‘Leonardo, I am most grateful. And I can pay you.’

‘I am grateful to you. This Codex of yours expands my knowledge – I fancied myself an innovator, but I find much in these ancient pages to intrigue me.’ He smiled, and murmured almost to himself. ‘And you, Ezio, cannot guess how indebted I am to you for showing them to me. Let me see any more that you may find – where they come from is your business. I am only interested in what they contain, and that no one else outside your inner circle, apart from me, should know about them. That is all the recompense I require.’

‘That is indeed a promise.’

‘Grazie! Until Friday, then – at sunset?’

‘Until Friday.’

Leonardo and his assistants discharged their commission well. The new weapon, though it was defensive in application, was extraordinarily useful. Leonardo’s younger assistants mock-attacked Ezio, but using real weapons, including double-handed swords and battle-axes, and the wristplate, light as it was and easy to wield, easily deflected the heaviest blows.

‘This is an amazing armament, Leonardo.’

‘Indeed.’

‘And it may well save my life.’

‘Let’s hope you get no more scars like the one across the back of your left hand,’ said Leonardo.

‘That is a last souvenir from an old… friend,’ said Ezio. ‘But now I need one more piece of advice from you.’

Leonardo shrugged. ‘If I can help you, I will.’

Ezio glanced over at Leonardo’s assistants. ‘Perhaps in private?’

‘Follow me.’

Back in the studio, Ezio unwrapped the slip of paper Mario had given him and handed it to Leonardo. ‘This is the person my uncle told me to meet. He told me it’d be no good to try to find him directly -‘

But Leonardo was staring at the name on the paper. When he looked up, his face was filled with anxiety. ‘Do you know who this is?’

‘I read the name – La Volpe. I guess it’s a nickname.’

‘The Fox! Yes! But do not speak it aloud, or in public. He is a man whose eyes are everywhere, but who himself is never seen.’

‘Where might I find him?’

‘It is impossible to say, but if you wanted to make a start – and be very careful – you should try the district of the Mercato Vecchio -‘

‘But every thief who isn’t either in gaol or on the gallows hangs out there.’

‘I told you you’d need to be careful.’ Leonardo looked round as if he were being overheard. ‘I… might be able to get word to him… Go and look for him tomorrow after Vespers… Perhaps you will be fortunate… perhaps not.’

Despite his uncle’s warning, there was one person in Florence whom Ezio was determined to see again. In all the time of his absence, she had never been far from his heart, and now the pangs of love had increased with the knowledge that she was not far away. He could not take too many risks in the city. His face had changed, become more angular, as he had grown both in experience and years, but he was still recognizable as Ezio. His hood helped, allowing him to ‘disappear’ in a crowd, and he wore it low; but he knew that, although the Medici now held sway, the Pazzi had not had all their teeth drawn. They were biding their time, and they would remain vigilant: of those two things he was certain, just as he was certain that if they caught him unawares, they would kill him, Medici or no Medici. Nevertheless, the following morning he could no more prevent his feet taking the way to the Calfucci mansion than he could have flown to the moon.