‘I was doing my practice,’ I said. In the weeks following the demolition of Skygarden Tower – with me on top of it – I’d been a key witness in three separate investigations, in addition to one by the Department of Professional Standards. I’d spent a great deal of each working day in interview rooms in various nicks around London including the notorious twenty-third floor of the Empress State Building where the serious investigations branch of the DPS keeps its racks and thumbscrews.

This meant that I’d gotten into the habit of getting up early to do my practice and get in some time in the gym before heading off to answer the same bloody question five different ways. It was just as well, since I hadn’t exactly been sleeping well since Lesley had tasered me in the back. By the start of August the interviews had dried up, but the habit – and the insomnia – had stuck.

‘Has there been a request for assistance?’ I asked.

‘With regard to the formal investigation, no,’ said Nightingale. ‘But where children are concerned we have certain responsibilities.’

There were two of them, both girls, both aged eleven, both missing from two separate family homes in the same village in North Herefordshire. The first 999 call had been at just after nine o’clock the previous morning and it first hit media attention in the evening when the girls’ mobile phones were found at a local war memorial over a thousand metres from their homes. Overnight it went from local to national and, according to the Today programme, large-scale searches were due to commence that morning.

I knew the Folly had national responsibilities in a sort of de facto under-the-table way that nobody liked to talk about. But I couldn’t see how that related to missing kids.

‘Regrettably, in the past,’ said Nightingale, ‘children were occasionally used in the practice of . . .’ he groped around for the right term, ‘unethical types of magic. It’s always been our policy to keep an eye on missing child cases and, where necessary, check to make sure that certain individuals in the proximity are not involved.’

‘Certain individuals?’ I asked.

‘Hedge wizards and the like,’ he said.

In Folly parlance a ‘hedge wizard’ was any magical practitioner who had either picked up their skills ad hoc from outside the Folly or who had retired to seclusion in the countryside – what Nightingale called ‘rusticated’. We both looked over to where Varvara Sidorovna Tamonina, formerly of the 365th Special Regiment of the Red Army, was sitting at her table on the other side of the breakfast room, drinking black coffee and reading Cosmopolitan. Varvara Sidorovna, trained by the Red Army, definitely fell into the ‘and the like’ category. But since she’d been lodging with us while awaiting trial for the last two months she, at least, was unlikely to be involved.