Nightingale had been carrying around a hard copy of the Piccini script. I laid it out and drew attention to the scene that followed Punch’s disposal of the blind beggar. In it the constable arrives to arrest Punch for murdering his wife and baby.

‘I make myself the constable in the next scene.’

‘You’re volunteering to have your head beaten in?’ asked Dr Walid.

‘If you read the script you’ll see that the constable actually survives the encounter,’ I said. ‘As does the officer who arrives immediately after.’

‘I take it that would be me,’ said Nightingale.

‘Just so long as it’s not me,’ said Lesley.

‘I’m not sure I can see this working,’ said Nightingale. ‘Henry Pyke has no reason to engineer an encounter with us, however well we fit his little play.’

Dr Walid put his finger on the script and said, ‘Punch asks, “And who sent for you?” to which the constable replies, “I’m sent for you.” Punch doesn’t get a choice; this is his destiny catching up with him. “I don’t want the constable,” he says.’

‘I think you’ve got Punch all wrong,’ said Lesley. ‘You’re assuming he’s like a kind of supernatural serial killer who’s locked into acting out a Punch and Judy show. But what if he’s something else?’

‘Like what?’ I asked.

‘Like the manifestation of a social trend, crime and disorder, a sort of super-chav. The spirit of riot and rebellion in the London mob.’

We all looked at her in amazement.

‘You forget I did A levels too, you know,’ said Lesley.

‘Do you have another plan?’ I asked.

‘No,’ said Lesley. ‘I just want you to be careful. Just because you think you know what you’re doing doesn’t mean you actually know what you’re doing.’

‘I’m glad we’ve clarified that,’ I said.

‘You’re welcome,’ she said. ‘Even if you catch up with Henry, what then?’

It was a good question – I looked at Nightingale.

‘I can track his spirit,’ said Nightingale. ‘If I get close enough I can track him all the way back to his old bones.’

‘And then what?’ asked Lesley.

I looked at Nightingale. ‘We dig them up and grind them into dust, mix them with rock salt and then scatter them out at sea,’ I said.

‘And that’ll work?’ she asked.

‘Has before,’ said Dr Walid.

‘You’ll need a warrant,’ said Lesley.

‘We don’t need a warrant for a ghost,’ I said.

Lesley grinned and pushed the script over to my side of the table. She tapped the page with her spoon and I read the line: Constable: Don’t tell me. You have committed murder, and I have a warrant for you. ‘If you want to play the part, you’re going to need all the props.’

‘A warrant for a ghost,’ I said.