‘I checked with Companies House,’ she said. ‘The Beale family business goes all the way back to Empire Pottery which, by the time it went effectively bust in the 1950s, was but a small adjunct of the seriously large property, construction and engineering subcontracting business. Matthew Carroll’s son William is listed as running the Dublin branch of the firm – now I know what you’re thinking, but guess who that kiln belonged to?’

‘Ryan Carroll.’

‘Correct,’ said Lesley and waved her notebook at me. ‘He’s using that warehouse rent-free, so either he has a direct family connection or the Beales are just sentimental about the name.’

‘Maybe we should interview Carroll.’ I said.

‘You think?’

‘Do you have a firm connection with James Gallagher?’ I asked.

‘You’re going to like this,’ she said.

Because, according to Lesley, US senators don’t have your common or garden blog pages they have huge fuck-off commercial-quality websites, plural, that tell you everything they need you to know about them. Or at least everything the senator needs you to know.

‘Although they don’t have a lot in the way of humorous cats,’ said Lesley.

But they did have a lot about Senator Gallagher’s family, including the story of Sean Gallagher who emigrated to America in 1864 to seek a new life of freedom, liberty and apple pie.

‘And to avoid arrest on suspicion of murder,’ said Lesley. ‘According to the court records. Glassed some guy in an establishment of the type frequented by ruffians, navvies and others of low character.’

‘Did he do it?’ I asked.

‘This was the old-fashioned coppering,’ said Lesley. ‘He was drunk and Irish and the victim was likewise drunk and Irish, they were known to be arguing but there were no witnesses to the actual killing. Everyone in the establishment having been struck suddenly blind and deaf. Although that might have had something to with the gin they were drinking. Anyway, his bail was stood by his brother Patrick and by Eugene Beale and it was them that paid when he did his flit to the States.’

Where he and his descendants became pillars of the notorious New York political system. Lesley didn’t know what it was notorious for, except that’s how it was always described – notorious.

What had we stumbled into in the sewers? A culture, a secret society? Nightingale would have to be told but Detective Chief Inspector Seawoll would want a great deal more ‘real’ evidence before he started bringing in people for questioning.

‘We need to check the mundane library,’ I said. ‘See if there’s anything about the tunnels dating back to before the 1940s.’

‘You know it’s Christmas Eve, don’t you?’ asked Lesley.

‘Really,’ I said. ‘Does this mean you want a present?’