‘She knows who we are,’ I said. ‘Which means she probably walked in with a plan.’

‘To what end?’ asked Nightingale.

‘It can’t be to spring her daughter,’ said Stephanopoulos. ‘Her brief’s going to have her out in less than two hours. We don’t have enough to charge her with anything more than making an affray and she’s going to maintain that she was out shopping when she was caught up in a police operation.’

‘That’s unfortunate,’ said Nightingale.

‘That’s the consequence of having a branch of the Met operating without statutory authority,’ said Stephanopoulos. ‘We can’t really explain to a jury that she obstructed the police in their lawful activity by shooting smoke out of her fingertips – can we?’

‘Quite,’ said Nightingale. ‘Which is why I’m going to take a leaf out of Peter’s book and invite them round for tea.’

‘Sir?’ I said and looked at Stephanopoulos, who shrugged.

‘Lady Helena clearly wants something from us, and equally clearly she has information it could profit us to know,’ he said. ‘I suggest we ask her – politely – what it is.’

‘So, tea this afternoon then?’

‘Good Lord no, Peter,’ he said. ‘Tomorrow afternoon at the very earliest. For one thing we need to gather as much intelligence on Lady Helena as we can, and I need to brief Postmartin about the ledger. But, most importantly, we must give Molly time to prepare for guests. If we spring a member of the aristocracy on her without warning it could go very badly for us indeed.’

So, in the classic manner of a swan, the top half glided effortlessly across the police work while below the surface me and Guleed scrambled to pull together a decent intelligence assessment of a woman who, if I’m any judge, learnt how to be bureaucratically invisible on her mother’s knee.

And how to heal with magic – possibly.

With all that implied.

And having made sure my attention was focused in one direction the universe, which likes a good laugh, smacked me in the face from the other side. Just as I was considering calling the Foreign and Commonwealth Office, formerly the Colonial Office, to see if they had anything on Lady Helena’s activities in Kenya, my phone rang and an American voice said, ‘Hi Peter, how you doing?’

It was Kim or, more formally, Special Agent Kimberley Reynolds of the FBI. We’d met a couple of years back when we’d engaged in competitive car tracking, suspect-losing and the world’s first three-person sewer-luge team. We’d exchanged maybe five emails apiece since then – mostly at Christmas. One had been to alert her to the change in Lesley May’s status.

‘Hi Kim,’ I said. ‘What’s up?’

‘You never write me, Peter,’ she said. ‘You never call – so I thought I’d see how you were doing.’