"No," I said. "I don't. Do you?"

He wouldn't say he didn't, but he didn't. He picked up the Lego box and marched off with it, and I went to look at the clothes in the garage.

Nothing was worth saving, I thought. All highly depressing. My jodhpur boots with the toes flattened, Malcolm's vicuna coats with triangular tears. I left it all as it lay and started out on a quick hike round the garden to make sure all was well with the gold, and came upon Arthur Bellbrook digging potatoes within six feet of it. My heart jumped a bit. His was undisturbed.

We exchanged good mornings and remarks about the weather. He asked what he should do with the potatoes and I told him to take them home. He nodded his thanks. He complained that the pick-up trucks for the rubbish skips were ruining the lawn. He said souvenir hunters had stripped Mrs Pembroke's fancy greenhouse of every single geranium, including the cuttings, but not to worry, without glass in the windows they would have died in the first frost. It had been a mild autumn, but frost would come soon.

He looked along the length of the kitchen garden, his back towards the end wall. He would dig everything over, he said, ready for winter. I left him bending again to his task, not sure whether he was a guardian of the gold or a threat to it. Malcolm had a nerve, I thought, hiding his stockpile in that place and seeing Arthur work close to it day after day. Malcolm had more nerve than was good for him.

I drove to the pub in Cookham, where they were getting used to my hours, took a bath, put on trousers, shirt and jersey and, accompanied by Norman West's notes, went down to the bar for a drink before lunch. I read:

Mr Thomas Pembroke (39) lives with his wife Berenice at 6 Arden Haciendas, Sonning, Nr. Reading, in the strip of new townhouses where old Arden House used to be. Two daughters (9 and 7) go to comprehensive school.

Mr T. used to work as quantity surveyor for Reading firm of biscuit makers, Shutleworth Digby Ltd. He got sacked for wrong estimates several weeks ago. I was told unofficially at the firm that he'd cost them thousands by ordering six times the glace cherries needed for a run of "dotted pinks". (Had to laugh!) No laughing matter when tons of sliced almonds turned up after "nut fluffs" had been discontinued. Mr T. didn't contest sacking, just left. Firm very relieved. Mr T. had been getting more and more useless, but had long service.

Mr T. didn't tell his wife he'd lost his job, but went off as if to work every day. (Common reaction.) On Newmarket Sales Tuesday he was "walking about", same as the previous Friday. Pressed, he says he probably went to the public library in Reading, he did that most days; also sat around wherever there were seats, doing nothing. He read the job-offer pages in newspapers, but apparently did little to find work. No heart. (My opinion.) Mr T. on brink of nervous breakdown (my opinion).

I interviewed him in coffee shop. His hands trembled half the time, rattling cup against teeth, and he's not yet forty. Alcohol? Don't think so. Nerves shot to hell.

Mr T. drives old grey Austin 1100. Has slight dent in front wing. Mr T. says it's been there weeks. Car dirty, could do with wash. Mr T. says he has no energy for things like that.

Mr T.'s opinion of Mr Ian is very muddled (like the rest of him). Mr Ian is "best of bunch, really", but also Mr T. says Mr Ian is Mr Pembroke's favourite and it isn't fair. End of enquiry.

With a sigh, I put Thomas to the back and read about Berenice; no happy tale.

Mrs Berenice Pembroke (44 according to Mrs Joyce), wife of Mr Thomas, lives at 6 Arden Haciendas. No job. Looks after daughters, spends her days doing housework and reading trashy romances (according to Mrs Joyce again!).

Mrs B. very hard to interview. First visit, nothing. Second visit, a little, not much. She couldn't produce alibi for either day.

I asked about children and school journeys. Mrs B. doesn't drive them, they go by bus. They walk alone along pavement in residential side-road to and from bus stop, which is about one-third of mile away, on the main thoroughfare. Mrs B's mother lives actually on the bus route. The girls get off the bus there most afternoons and go to their grandmother's for tea.

Interviewed Mrs B.'s mother. Not helpful. Agreed girls go there most days. Sometimes (if cold, wet or dark) she drives them home at about 7 pm. Other days, they finish journey by bus. I asked why they go there for tea so often and stay so late. Told to mind my own business. Younger girl said Granny makes better teas, Mummy gets cross. Told to shut up by older girl. Mrs B.'s mother showed me out.

Mrs B. drives old white Morris Maxi, clean, no marks on it.

Mrs B. gave no opinion of Mr Ian when asked, but looked as if she could spit. Says Mr Pembroke is wicked. Mrs B. slammed her front door (she hadn't asked me in!). End of enquiry.

I put Berenice, too, back in the packet, and cheered myself up just a fraction with a slice of pork pie and a game of darts.

From the outside, Arden Haciendas were dreadful: tiny houses of dark brown-red brick set at odd angles to each other, with dark- framed windows at odd heights and dark front doors leading from walled front gardens one could cross in one stride. Nevertheless, Arden Haciendas, as Joyce had informed me a year earlier when Thomas had moved there, were socially the in thing, as they had won a prize for the architect.

God help architecture, I thought, ringing the bell of No 6. I hadn't been to this house before: had associated Thomas and Berenice always with the rather ordinary bungalow they'd bought at the time of their wedding.

Berenice opened the door and tried to close it again when she saw me, but I pushed from my side and put my shoe over the threshold, and finally, with ill grace, she stepped back.

"We don't want to see you," she said. "Dear Thomas isn't well. You've no right to shove your way in here. I hate you."

"Well, hate or not, I want to talk to Thomas."

She couldn't say he wasn't there, because I could see him. Inside, the Haciendas were open-plan with rooms at odd angles to each other, which explained the odd-angled exteriors. The front door led into an angled off-shoot of the main room, which had no ceiling where one would expect it, but soared to the rafters. Windows one couldn't see out of let daylight in at random points in the walls. Horrible, I thought, but that was only, as Mr West would say, my opinion.

Thomas rose to his feet from one of the heavily-stuffed armchairs brought from the bungalow, old comfortable chairs looking incongruous in all the aggressive modernity. There was no carpet on the woodblock floor; Thomas's shoes squeaked on it when he moved.

"Come in, old chap," he said.

"We don't want him," Berenice objected.

Thomas was looking haggard and I was shocked. I hadn't seen him, I realised, for quite a long time. All youth had left him, and I thought of him as he had been at eighteen or nineteen, laughing and good-humoured, coming for weekends and making Serena giggle. Twenty years on, he looked middle-aged, the head balder than when I'd last taken his photograph, the ginger moustache less well tended, the desperation all-pervading. Norman West's assessment of early breakdown seemed conservative. It looked to me as if it had already happened. Thomas was a lot further down the line to disintegration than Gervase.

Ferdinand, he confirmed in answer to my question, had told him about Malcolm's will and about Malcolm's wish that I should try to find out who wanted to kill him. Thomas couldn't help, he said. I reminded him of the day old Fred blew up the tree stump. Ferdinand had mentioned that too, he said. Thomas had been there. He remembered it clearly. He had carried Serena on his shoulders, and Fred had been blown flat.

"And do you remember the time-switches we used to make, with wire on the clocks' hands?"