I found Guleed still in the car reading something off her phone. She’d taken the opportunity to change her hijab, the new one being electric blue with silver and black details. Hijabs, Guleed once told me, were like T-shirts – you could choose ones that uniquely expressed your personality. But, unlike a T-shirt, you could wear them with the sort of conservative suit that was de rigueur for serving police officers.

‘Do you get the impression that this Phoebe is more involved with the dead girl and Reynard than Tyburn’s daughter is?’ asked Guleed, once I’d filled her in.

‘Just a bit,’ I said. ‘We’ll have to ask.’

We were already heading for Phoebe Beaumont-Jones’ address in St Johns Wood. She lived just west of Primrose Hill, part of that band of posh that runs down from Hampstead Hill in the north to Mayfair in the south. Along the line, I couldn’t help notice, of the hidden river Tyburn. My dad says that when he was younger these areas used to have all sorts of people, but the artists, musicians and other undesirables had been leached out by London’s continuous house price boom.

I was pretty certain that, ten seconds after I’d left her house, Olivia would have phoned or texted Phoebe to let her know we were on our way, and we needed to at least have the house under surveillance in case she tried to leg it.

But before we got there Nightingale called and said that he and Lady Helena had found Reynard Fossman.

‘Where is he?’ I asked.

‘He’s gone to ground in Archway – at the Intrepid Fox.’

‘Seriously?’

‘Perhaps,’ said Nightingale, ‘he felt that its very obviousness would be deception enough.’

Obviously not very experienced with the police then – we like obvious. Obvious is our middle name.

Since this was going to be an all-Falcon, plus ambiguous auxiliaries, operation Nightingale needed me immediately. Guleed promised she’d sit on Phoebe’s house until I had a chance to get back.

‘It’s all go in the Isaacs, isn’t it?’ she said.

‘Where’d you get that name from?’ I asked.

‘Isn’t that what the Folly is called?’ said Guleed. ‘I’m sure I heard that somewhere.’

‘You’ve been talking to Bev, haven’t you?’

‘That would be telling,’ she said. So, yeah, she’d been talking to Bev.

God, I hoped it was Bev. Because if it was someone else—

Guleed dropped me off at Warren Street so I could get the tube to Archway.