He rapped his knuckles against the last name on the door.

‘Watch out for Eddie Tangiers. Big guy, strong as an ox – I lured him in here only a week ago. Used a trail of fruit gums, if you’re interested. Not quite as effective as marshmallows, but less bulky to carry – and more economic.’

‘Good tip. Thanks. How will I know him?’

‘Oh, you’ll know him: kind of big, kind of dead, kind of needs to be avoided. Good luck. The Sno-Trac will be on your left, fifty yards in.’

After pausing to listen at the door, Lloyd pulled back the spring-loaded door bolt, opened the door and then fired the flashgun. There was a bright flash in which happily a nightwalker was not revealed, and a waft of warm air greeted us from the semi-gloom, and with it the smell of decomposition. Lloyd hurriedly ejected the spent bulb and pushed in another from his pocket.

‘One or two are definitely greeners,’ he said, wrinkling his nose. ‘Maybe I didn’t feed them enough Weetabix. ’

I stepped in and snapped on my flashlight. A meagre light filtered down the light-wells by which I could see the general layout of the basement: doughnut-shaped around the central core, with sturdy brick vaulting to support the building above. Serried ranks of cars, motorbikes, trucks, haywains and agricultural equipment, most covered by dustsheets, were parked in two rows with access along the inside radius. I paused for a moment, but Lloyd didn’t; I heard the door clang shut and his footsteps retreated rapidly back up the stairs.

I found the Sno-Trac with ease, but it wouldn’t be going anywhere. Someone had left the compressed air tank open and the air had leaked out – there was nothing to start the engine. I paused for thought and then decided to exit by way of the ramp and then have a scout around outside whilst I figured out my options.

I trod silently along the rows of vehicles. Not because I didn’t want the deadheads to know I was here, I just wanted to hear them first. About a third of the way around the basement and with the exit just visible on the far side, I came across the first nightwalker but it was now little but bones, picked clean.