The Girdlers’ Chapel. And this must be the Smiths’ Chapel. There was no sign of the parclose screen. I tried to judge how far from the windows it would have stood, and started digging.

The bishop’s bird stump wasn’t underneath the mass of twisted girders and broken stone, and neither was the parclose screen. A broken-off length of kneeling rail was, and part of a pew, which meant I was too far out into the nave.

I stood up, trying to orient myself. It’s amazing how much destruction can distort the sense of space. I knelt down and looked up the church toward the choir, trying to spot the base of any of the north aisle pillars to see how far out into the nave I was, but they were hopelessly buried.

I needed to find where the arch had been and work from there. I looked back up at the Girdlers’ Chapel’s east wall, aligned myself with it and the windows, and started digging again, looking for the supporting pillar of the arch.

It had been broken off six inches from the floor. I uncovered the space around it, then, sighting along it, tried to estimate where the screen would have been, and started digging again.

Nothing. I heaved up a jagged piece of the wooden ceiling, and under it was a giant slab of marble, cracked across. The altar. Now I was too far in. I sighted along the new recruit again, who was still watching Mr. Spivens dig, paced off ten feet, and started digging again.

“But we are from the AFS,” I heard Carruthers say to the verger.

“Are you certain you’re with the AFS?” the verger said. “Those coveralls don’t look like any AFS uniform I’ve ever seen.”

He wasn’t having any of it, and no wonder. Our uniforms had been intended for the middle of an air raid, when anyone in a tin helmet can pass for official. And for the middle of the night. Daylight was another matter. Carruthers’s helmet had a Royal Engineers insignia, mine was stencilled “ARP” and the new recruit’s was from another war altogether.