‘And the second L is the Federal Reserve Bank that printed it. There are loads of them, Dallas, New York, Virginia. L stands for San Francisco. You can see here, too, under the serial number, it says L12. So it’s definitely the San Francisco Fed that printed it.’ I dropped the match before it burned my fingers and the note dissolved back into the shadows. ‘Except they didn’t.’

‘Didn’t what?’

‘Print it.’

‘I don’t understand.’ It was hard to make out his expression, but the glow of the night lights in the bar caught in the corners of his eyes. ‘How could you know that? Actually,’ I lit another cigarette, ‘how do you know any of this?’

‘I asked a good friend of mine.’

‘I see. And who is your friend?’

‘Professor Google. He’s, like, totally amazing. You can ask him anything.’

‘Are you fucking with me?’

‘No! You can check it yourself, Max, seriously. Did you see the other letter, after the serial number? It’s a J. That series of bill was actually printed in 2013. Except that bill wasn’t, couldn’t have been, because the LL J notes end at LL 44800000.’

‘So, the numbers and the letters don’t match up?’

He peered at me with a look that mingled pity with incredulity. ‘Correct.’

‘And that, combined with the fact that the serial number is a right …’ I searched for the term I’d already forgotten, ‘prime – this special number – made you get on a flight?’

‘No.’

‘No?’

‘No. Ezra made me get on the flight. He wanted me to come and find you.’

‘Ezra told you to find me?’ It was a lot to take in. ‘And why did he do that?’

‘Because he has a message for you that I don’t think he wants Talia or her friends to know about. He said I should tell only you.’ He paused for a moment. ‘Should I tell you now?’

‘Yes, Baaz.’ My own voice was rising, too. I took a deep breath. ‘You should tell me now.’

‘OK.’ He cleared his throat, every inch the messenger arrived from Marathon with news of victory. ‘Ezra told me to tell you that you must visit Moshe Mendel Katz in Mea She’arim.’ He paused again, and then added, less formally: ‘About the banknote, I mean. Ezra says he knows a lot about money.’

I pinched the sleep out of my eyes with my left thumb and index finger.

‘And why didn’t you mention this when you arrived?’