I joined him at the window. It was getting light and a thick mist was washing out the trees and pastures of Hyde Park and the city beyond. Seawoll pointed down to a pair of statues in the faux garden at the back of the estate – two bronze heads that looked like they’d been flattened in a Corby trouser press and then had their brains scooped out.

‘It’s called Waiting For Enlightenment,’ said Seawoll, looking at the statues. ‘But if you ask me it’s a fucking rip-off of The Foothills of the Headlands from Yellow Submarine.’ Which meant nothing to me. ‘God, money is so wasted on the rich.’

‘Do you want me to statement Olivia McAllister-Thames?’ I asked.

‘No,’ he said. ‘I want Sahra to do that.’ He waved airily back at the flat. ‘Have you had a chance to check for any tingles?’

I said, with some dignity, that I had done an initial Falcon assessment and found nothing that indicated that a supernatural event had taken place on the premises.

‘Thank Christ for that,’ said Seawoll. ‘In that case you can go with Guleed and make sure nothing weird happens to her.’

Seawoll, like most of the senior officers who were aware of the Folly, might not like me using the M-word. But they weren’t about to ignore anything that might have an impact at an operational level. It’s understandable. You may not want to dwell on the fact that eighty percent of infant homicides are committed by the parents, but you’re still going to make the grieving mum and dad your prime suspects until proved otherwise.

‘In fact,’ he said, ‘I’m making you personally fucking responsible for making sure nothing weird happens to her. If you can’t guarantee that, I want your boss down here to do the job instead – understand?’

‘Yes, guv,’ I said.

Guleed always claimed that she’d joined the police on a dare. ‘My sister bet me I wouldn’t send off the application,’ she’d told me when we’d been doing the thing with the haunted BMWs, ‘but I didn’t think I’d be accepted.’ When I’d asked about the mandatory interview, she said she’d had nothing better to do that day. ‘What did your parents think?’ I’d said.

‘They thought the starting salary was a bit on the low side.’

‘What about your friends?’ I’d asked, and Guleed had changed the subject.

Guleed was one of Seawoll’s favoured few, one of his Valkyries. And he was determined to push her up the fast track. Sending her off to handle a tricky interview like the one with Olivia McAllister-Thames was part test, part toughening exercise, and part vote of confidence.