‘I put in some Gulder,’ I said. ‘Some Red Stripe for variety, a couple of cases of Bacardi, some Appleton, Cointreau and a few bottles of Bailey’s.’ I’d liquidated my savings doing it, but as my mum says, nothing worth having is free.

‘That’s a handsome gift,’ said Mama Thames.

‘You can’t be serious?’ said Tyburn.

‘Don’t worry, Ty,’ I said. ‘I threw in a couple of bottles of Perrier for you.’

Someone sniggered – probably Beverley.

‘And what can I do for you?’ asked Mama Thames.

‘It’s a small matter,’ I said. ‘One of your daughters feels that she has a right to interfere in the business of the Folly. All I ask is that she steps back and lets the proper authorities get on with their jobs.’

‘Proper authorities,’ spat Tyburn.

Mama Thames turned her eyes on Tyburn, who stepped before the throne. ‘You think you have a right to meddle in this?’ she asked.

‘Mum,’ said Tyburn. ‘The Folly is a relic, a Victorian afterthought from the same people who gave us Black Rod and the Lord Mayor’s show. Heritage is all very well and good for the tourist industry, but it’s no way to run a modern city.’

‘That is not your decision to make,’ I said.

‘And you think it’s yours?’

‘I know it’s mine,’ I said. ‘My duty, my obligation – my decision.’

‘And you’re asking—’

‘I am not asking,’ I said, pleasantries over. ‘You want to fuck with me, Tyburn, you had better know who you’re messing with.’

Tyburn took a step back and recovered. ‘We know who you are,’ she said. ‘Your father is a failed musician and your mother cleans offices for a living. You grew up in a council flat, and you went to your local comprehensive and you failed your A levels …’

‘I am a sworn constable,’ I said, ‘and that makes me an officer of the law. I am also an apprentice, which makes me a keeper of the sacred flame, but most of all I am a free man of London and that makes me a Prince of the City.’ I jabbed a finger at Tyburn. ‘No double first from Oxford trumps that.’

‘You think so?’ she said.

‘Enough,’ said Mama Thames. ‘Let him into his house.’

‘It’s not his house,’ said Tyburn.

‘Do as I say,’ said Mama Thames.

‘But Mum …’

‘Tyburn!’