I didn’t like to commit without corroboration, but I was willing to bet that whatever had happened to the phones had happened right where I was standing.

‘This is the place,’ I said.

‘Are you sure?’ asked Dominic.

‘Edmondson’s going to want a POLSA up here,’ I said. ‘Before it gets dark.’

Dominic pulled out his phone and called in to the nick while I did a slow turn on the spot to see whether anything jumped out. Up on the ridge there was a cool breeze that lazily stirred the grass and the odd clump of bracken. I could hear bird song and far in the distance the lawn-mower hum of a power tool. The sky was powder blue and cloudless – not even a contrail.

I heard Dominic explaining to Windrow that I was certain that the phones had been abandoned at this particular spot. I noticed he didn’t mention the M word or call it Falcon. Nightingale says that conspiracies of silence are the only kind of conspiracies that stand the test of time.

‘Is this place important?’ I asked Russell.

‘It’s the Whiteway Head,’ said Russell. ‘This is where all the ancient track-ways cross.’

If I squinted at the dry yellow grass I could sort of see what he meant. The Mortimer Trail came out of its gate and ran west to east, and there was definitely another track crossing it north to south. I went to where I judged the centre of the crossroads was, got on my hands and knees and lowered my face towards the grass.

I was briefly distracted by Russell asking Dominic whether I was praying to Mecca, but I’ve done this procedure at Piccadilly Circus so it was only for a moment. The short grass was prickly under my palms and filled my nostrils with its vaguely sick-making smell. I idly chased Beverley across the meadows of my mind before letting that go and for a moment I thought there was nothing to sense.

Then suddenly I felt it. Very quiet but very deep, the crack-crack of chisels in stone and the heavy slap of men carrying weight on their shoulders, grunting and sweating and the thirsty smell of salt. You do get vestigia in the countryside, I thought, only it seeps in deep and lies there like water under a dry riverbed.

And there was something else, a greasy tension that I remembered from when the Stadtkrone broke open at the top of Skygarden Tower and filled the air with magic. The Romantics had been right. There was power out here amongst all the green stuff – Polidori’s potentia naturalis.

I broke out Dominic’s map. Stan’s raided stash was down the Mortimer Trail to the west, Rushpool was along the track to the south, and across a valley to the north at the top of the next ridge was Hugh Oswald’s house – less than fifteen hundred metres as the bee flies.