"Kind of high-profile here, aren't we?" I ask McDunn.

"Mm-hmm," is all he'll say.

We come to the village. I look up at our old house; bushes and trees are taller. Satellite dish. Conservatory on one side. I watch the familiar shops and houses go by; Mum's old gift shop (now a video shop); the Arms, where I had my first pint; Dad's old garage, still doing business. Another police car, parked on the village green. "Will the Goulds be at the house?" I ask.

McDunn shakes his head. "They're in that hotel we just passed."

I'm relieved. I don't think I'd know what to say to them. Hi; the good news is I didn't kill your son, in fact he isn't dead at all, but the bad news is he's a multiple murderer.

Five minutes later we're at the house.

The gravel circle outside the house looks like the car park at a cop convention. I hear a clattering in the air as McDunn gets out of the Jag and I look up over the trees into high, bright overcast. Fuck me, they've even brought a chopper.

McDunn stands talking to some heavily brassed uniformed cops on the steps of the front door. I look round the old place; the window surrounds have been painted, the flower-beds look a bit unkempt. Nothing else has changed; I haven't been here since that day a week after Clare died, and it had the same muddily washed-out look about it then.

McDunn comes back towards the car, catches FlavelPs eye and beckons him. We get out and follow McDunn into the house.

Nothing much different inside, either; still looks and smells the same: polished parquet flooring, sumptuous but fading old rugs, assorted mostly very old furniture, lots of big houseplants on the floor and time-dulled landscapes and portraits on the wood-panelled walls. We walk under the angle of the main staircase, into the dining room. The place is full of cops; there's a map of the estate on the table, almost covering it. McDunn introduces me to the other officers. I have never had so many hard, suspicious looks in my life.

"So, where's this body?" one of the uniformed guys from Strathclyde asks. He's here because they've loaned the helicopter.

"Still here," I tell him. "Unlike… unlike the man you're looking for." I look at McDunn, the one friendly-ish face in here and the only one I can look at without feeling like a five-year-old who's just wet his pants. "I thought the idea was to let the funeral go ahead, or at least make it look like it was; he was bound to be here. You might have caught him then."

McDunn's face gives a good impression of being stone-clad. "That was not felt to be the most suitable way of proceeding in this matter," he says, sounding like a police spokesman for the first time.

There's a sensation of well tailored black uniforms rustling in the room and I get the impression from the general atmosphere and a few exchanged looks that this is a contentious point.

"We're still waiting for this body," says the man with the braid from Tayside, the boys officially in charge. "Mr Colley," he adds.

I look down at the map of the estate. "I'll show you," I tell them. "You'll need a… crowbar or something, about fifty metres of rope and a torch. A hacksaw might be handy, too."

Andy reaches up to the iron grating and pulls at it.

"This one comes away," he grunts; his voice is still shaky.

I help him; we lift the rusting grating up at one end but the far side is still secured by an iron pin and we can't shift it any further.

Andy takes the branch we hit the man with and wedges it under the grating; part of it sticks through but there's a stump where a smaller branch has broken off and the grating rests on that, held a half-metre or so off the stone rim.

Andy throws the man's rucksack into the shaft, then bends and takes the man under one armpit, trying to heave him up.

"Come on!" he hisses.

We haul the man up, his back against the stone of the vent, his head flopping down onto his chest. There's a little blood on the stones of the chimney. Andy takes the man's calves under his armpits and lifts; I get underneath and force the man's shoulders up; his head goes over onto the stone rim of the vent, beneath the grating. We both push and heave and the man's shoulders scrape over the rim; his arms drag up and over as Andy pushes, grunting, feet slipping on the old leaves and soil. I push the man's behind up, lifting with all my might. The man's trousers snag on the stone and start to come down again, then the branch holding the grating shirts and the iron grid falls down, thumping into the man's chest.

"Shit," Andy breathes. We struggle to lift the grating up and wedge the branch underneath again. The man's head is poised over the shaft, drooping down into it. We push his legs but they buckle at the knees, so we have to hold them up above our heads as we push to make them stay straight, then as we shove and his trousers are rolled down by the rim of stone, his arms flop over the far side of the shaft rim and it suddenly gets easier to push him. He slides out of our grasp, slipping into the shaft with a scraping noise. His trousers bunch round his ankles again, then catch round his boots and disappear over the edge of the chimney, kicking up at the last moment and hitting the grating; the branch slips and the grating slams down. The branch falls through it into the shaft and drops after the man.

We stand there for a second or two. Then there is — unless we each imagine it — a very faint thump. Andy suddenly jerks into motion and scrambles up onto the rim of the chimney. He stares through the grating, down into the darkness.

"Can you see him?" I ask.

Andy shakes his head. "But let's get some branches anyway," he says.

We prop the grating open with another branch and spend the next half-hour pulling fallen branches and logs from all over that part of the hill, dragging them into the clump of bushes and throwing them into the shaft; we snap dead branches off trees and bushes and haul and peel living ones off; we scrape together armfuls of dry leaf litter and throw those over the edge of the chimney, too; everything goes under the grating and down into the shaft. We still can't see anything down there.

Eventually a large branch with lots of other branches on it and lots of leaves — half a bush, practically — snags only a few metres down the shaft and we stop, breathless, sweating, trembling from exertion and delayed shock. We let the grating fall back and throw the last branch down into the darkness; it catches on the branches stuck near the top of the shaft. We sit on the dead leaves at the foot of the vent, backs against the stone.

"Are you all right?" I ask Andy after a while.

He nods. I put a hand out to him but he flinches again.

We sit there for some time but I keep glancing up, and gradually become terrified that the man is somehow not dead or has become a zombie and is climbing back up the shaft towards us, to push the grating up and put his already rotting hands down and grab us both by the hair. I stand up and face Andy. My legs are still shaky and my mouth has gone very dry.

Andy stands too. "A swim," he says.

"What?"

"Let's — " Andy swallows. "Let's go for a swim. Down to the loch, the river." He glances back at the stones of the air shaft.

"Yeah," I say, trying to sound cheerful and unconcerned. "A swim." I look at my hands, all scraped and dirty. There's some blood on them. They're still shaking. "Good idea."

We crawl out of the undergrowth into the bright day.

There are a few minutes, perhaps not more than three or four, when I exist in a bewildering storm of hope, joy, incomprehension and dread, when they don't find the body at the bottom of the shaft.

We walked here through the gardens and the woods, past the hill where Andy and I lay in the sunlight all those summers ago, into the little glen, then up through the bushes and the dead auburn wreckage of the ferns, to the trees at the summit of the small hill. A damp wind blew from the west, shaking drips off the high, bare trees and taking the sound of the main road away.