Wexford looked dubious. ‘Well, we won’t dismiss it as a theory. If he had contaminated the rest of the stew and others had been ill, that would have made it look even more like an accident, which was presumably what he wanted. But there’s one drawback to that, Mike. If he meant Hannah to die, and was unscrupulous enough not to mind about Corinne and Hood being made ill, why did he rinse the plates? To prove that it was an accident, he would have wanted above all to keep some of that stew for analysis when the time came, for analysis would have shown the presence of poisonous as well as non-poisonous fungi, and it would have seemed that he had merely been careless.

‘But let’s go and talk to these people, shall we?’

The shop called Harvest Home was closed. Wexford and Burden went down an alley at the side of the block, passed the glass-doored main entrance, and went to the back to a door that was labelled Stairs and Emergency Exit. They entered a small tiled vestibule and began to mount a steepish flight of stairs.

On each floor was a front door and a door to the lift. There was no one about. If there had been and they had had no wish to be seen, it would only have been necessary to wait behind the bend in the stairs until whoever it was had got into the lift. The bell by the front door on the fifth floor was marked A. and H. Kingman. Wexford rang it.

The man who admitted them was smallish and mild-looking and he looked sad. He showed Wexford the balcony from which his wife had fallen. It was one of two in the flat, the other being larger and extending outside the living-room windows. This one was outside a glazed kitchen door, a place for hanging washing or for gardening of the window-box variety. Herbs grew in pots, and in a long trough there still remained frost-bitten tomato vines. The wall surrounding the balcony was about three feet high, the drop sheer to the hard-top below.

‘Were you surprised that your wife committed suicide, Mr Kingman?’ said Wexford.

Kingman didn’t answer directly. ‘My wife set a very low valuation on herself. When we got married I thought she was like me, a simple sort of person who doesn’t ask much from life but has quite a capacity for contentment. It wasn’t like that. She expected more support and more comfort and encouragement than I could give. That was especially so for the first three months of our marriage. Then she seemed to turn against me. She was very moody, always up and down. My business isn’t doing very well and she was spending more money than we could afford. I don’t know where all the money was going and we quarrelled about it. Then she’d become depressed and say she was no use to me, she’d be better dead.’