He found himself in what looked like a catacomb corridor, but, as he cautiously advanced, the rough walls and dirt floor gave way to smoothly dressed stone and a marble floor that would not have disgraced a palace. And the walls glowed with a pale, supernatural light.

He was weak from his wound but he forced himself onwards, fascinated, and more awed than scared, though he was still on his guard, for he knew the Borgia had passed this way.

At last the passageway opened into a large room. The walls were smooth as glass and glowed with the same blue iridescence he’d seen earlier, only here it was more intense. In the centre of the room was a pedestal, and on it rested, in holders clearly designed for them, the Apple and the Staff.

The rear wall of the room was punctuated with hundreds of evenly spaced holes, and before it stood the Spaniard, desperately pushing and poking at the wall, oblivious of Ezio’s arrival.

‘Open, damn you, open!’ he cried in frustration and rage.

Ezio came forward. ‘It’s over, Rodrigo,’ he said. ‘Give it up. It doesn’t make sense any more.’

Rodrigo spun round to face him.

‘No more tricks,’ said Ezio, releasing his own daggers and throwing them down. ‘No more ancient artefacts. No more weapons. Now… let’s see what you’re made of, Vecchio.’

A smile slowly suffused Rodrigo’s debauched and broken face. ‘All right – if that’s how you want to play it.’

He shook off his heavy outer robe and stood in his tunic and hose. A fat, but compact and powerful body, over which little bolts of lightning raced – gained from the power of the Staff. And he stepped forward and landed the first blow – a vicious uppercut to Ezio’s jaw that sent him reeling. ‘Why couldn’t your father leave well enough alone?’ asked Rodrigo sorrowfully as he raised his boot to kick Ezio hard in the gut. ‘He just had to keep pursuing it, though… And you’re just like him. All you Assassins are like mosquitoes to be swatted. I wish to God that idiot Alberti had been able to hang you along with your kinsmen twenty-seven years ago.’

‘The evil resides not with us but with you, the Templars,’ rejoined Ezio, spitting out a tooth. You thought the people – ordinary, decent folk – were yours to play with, to do with as you pleased.’

‘But my dear fellow,’ said Rodrigo, getting a body-blow in under Ezio’s ribs, ‘that is what they are there for. Scum to be ruled and used. Always were, always will be.’

‘Stand off,’ panted Ezio. ‘This fight is immaterial. A more vital one awaits us. But tell me first, what do you even want with the Vault that lies beyond that wall? Don’t you already have all the power you could possibly need?’

Rodrigo looked surprised. ‘Don’t you know what lies within? Hasn’t the great and powerful Order of the Assassins figured it out?’

His torvid tone stopped Ezio in his tracks. ‘What are you talking about?’

Rodrigo’s eyes glittered. ‘It’s God! It’s God who dwells within the Vault!’

Ezio was too astonished to reply immediately. He knew that he was dealing with a dangerous madman. ‘Listen, do you really expect me to believe that God lives beneath the Vatican?’

‘Well, isn’t that a slightly more logical location than a kingdom on a cloud? – Surrounded by singing angels and cherubim? All that makes for a lovely image, but the truth is far more interesting.’

‘And what does God do down here?’

‘He waits to be set free.’

Ezio took a breath. ‘Let’s say I believe you – what do you think He’ll do if you manage to open that door?’

Rodrigo smiled. ‘I don’t care. It certainly isn’t His approval I’m after – just His power!’

‘And do you think He’ll give it up?’

‘Whatever lies behind that wall won’t be able to resist the combined strength of the Staff and the Apple.’ Rodrigo paused. ‘They were made for felling gods – whatever religion they belong to.’

‘But the Lord our God is meant to be all-knowing. All-powerful. Do you really think a couple of ancient relics can harm him?’

Rodrigo gave a superior smile. ‘You know nothing, boy. You take your image of the Creator from an old book – a book, mark you, written by men.’

‘But you are the Pope! How can you dismiss Christianity’s central text?’

Rodrigo laughed. ‘Are you really so naïve? I became Pope because the position gave me access. It gave me power ! Do you think I believed a single goddamned word of that ridiculous Book? It’s all lies and superstition. Just like every other religious tract that’s been written since people learned how to put pen to paper!’

‘There are those who would kill you for saying that.’

‘Perhaps. But the thought wouldn’t disturb my sleep.’ He paused. ‘Ezio, we Templars understand humanity, and that is why we hold it in such contempt!’

Ezio was speechless, but he continued to listen to the Pope’s ranting.

‘When my work here is finished,’ Rodrigo went on, ‘I think my first order of business will be dismantling the Church, so that men and women may finally be forced to assume responsibility for their actions, and at last be properly judged!’ His face became beatific. ‘It will be a thing of beauty, the new Templar world – governed by Reason and Order…’

‘How can you speak of reason and order,’ interrupted Ezio, ‘when your entire life has been governed by violence and immorality?’

‘Oh, I know I am an imperfect being, Ezio,’ simpered the Pope. ‘And I do not pretend otherwise. But, you see, there is no prize awarded for morality. You take what you can get and hold on tight to it – by any means necessary. After all,’ he spread his hands, ‘you only live once!’

‘If everyone lived by your Code,’ said Ezio, aghast, ‘the entire world would be consumed by madness.’

‘Exactly! And as if it hadn’t been already!’ Rodrigo jabbed a finger at him. ‘Did you sleep through your history lessons? Only a few hundred years ago or so our ancestors lived in muck and mire, consumed with ignorance and religious fervour – jumping at shadows, afraid of everything.’

‘But we have long since emerged from that and become both wiser and stronger.’

Rodrigo laughed again. ‘What a pleasant dream you have! But look around you. You have lived the reality yourself. The bloodshed. The violence. The gulf between the rich and the poor – and that is only growing wider.’ He fixed his eyes on Ezio’s. ‘There will never be parity. I’ve made my peace with that. You should, too.’