Lisa seemed to have forgotten his engagement to dine with Zoe. She didn’t mention it, so he didn’t either. On the following morning she was to leave with her mother for the month’s holiday the doctor had recommended for Mrs Cleasant’s health.

‘I wish I wasn’t going,’ she said to Peter. ‘You don’t know how I’ll miss you.’

‘Shan’t I miss you?’

‘Take care of yourself. I’ll worry in case anything happens to you. You mustn’t laugh, but when my father was alive and went away from us, I used to listen to the news four or five times a day in case there was a plane crash or a disaster.’

‘You’re the one that’s going away, Lisa.’

‘It comes to the same thing.’ She put up her hand to the charm she wore. ‘I’ve got this, but you . . . Would you take my four-leaved clover if I gave it to you?’

‘I thought you’d given up all that nonsense,’ he said, and his disappointment in her soured their farewells. She kissed him good-bye with a kind of passionate sadness.

‘Write to me,’ she said. ‘I’ll write every day.’

Her letters started coming at the end of the first week. They were the first he had ever had from her and they were like school essays written by a geography student, with love messages for the class teacher inserted here and there. They left him unsatisfied, a little peevish. He was lonely without her, but frightened of the image of her he carried with him. He needed someone with whom to talk it over and, after a few days of indecision, he telephoned Zoe. Ten minutes later he was in her flat, drinking her coffee and listening to her music. To be with her was a greater comfort than he had thought possible, for in the turn of her head, a certain way of hers of smiling, the way her hair grew from a widow’s peak on her forehead, he caught glimpses of Lisa.

And yet on that occasion he said nothing of his fears but ‘I can’t understand why I thought you and Lisa weren’t alike.’

‘I didn’t see it.’

‘It’s almost overpowering, it’s uncanny.’

She smiled. ‘If it helps you to come and see me to get through the time while she’s away, that’s all right with me, Peter. I can understand that I remind you of her and that makes things easier for you.’

‘It isn’t only that,’ he said. ‘You mustn’t think it’s only that.’

She said no more. It wasn’t her way to probe, to hold inquisitions, or to set an egotistical value on herself. But the next time they were together, he explained without being asked, and his explanation was appalling to him, the words more powerful and revealing than the thoughts from which they had sprung.

‘It isn’t true you remind me of Lisa. That’s not it. It’s that I see in you what she might become, only she never will.’