‘He won’t answer,’ I said. ‘I wouldn’t have told you if I’d thought it was going to upset you.’

She didn’t say any more. There were things cooking on the stove and the table was half-laid, but she left all that and went into the hall. Almost immediately afterwards I heard the front door close.

I know I’m slow on the uptake in some ways but I’m not stupid. Even a husband who trusts his wife like I trusted mine – or, rather, never considered there was any need for trust – would know, after that, that something had been going on. Nothing much, though, I told myself. A crush perhaps on her part, hero-worship which his flattery and his confidences had fanned. Naturally, she’d feel let down, betrayed, when she discovered he’d deceived her as to his where abouts when he’d led her to believe she was a special friend and privy to all his secrets. But I went upstairs just the same to reassure myself by looking in that dressing table drawer where she kept her souvenirs. Dishonourable? I don’t think so. She had never locked it or tried to keep its contents private from me.

And all those little mementoes of our first meeting, our courtship, our marriage, were still there. Between a birthday card and a Valentine I saw a pressed rose. But there too, alone in a nest made out of a lace handkerchief I had given her, were a locket and a button. The locket was one her mother had left to her, but the photograph in it, that of some long-dead unidentifiable relative, had been replaced by a cut-out of Reeve from a snapshot. On the reverse side was a lock of hair. The button I recognized as coming from Reeve’s blazer, though it hadn’t, I noticed, been cut off. He must have lost it in our house and she’d picked it up. The hair was Reeve’s, black, wavy, here and there with a thread of grey, but again it hadn’t been cut off. On one of our visits to his flat she must have combed it out of his hairbrush and twisted it into a lock. Poor little Gwendolen . . . Briefly, I’d suspected Reeve. For one dreadful moment, sitting down there after she’d gone out, I’d asked myself, could he have . . .? Could my best friend have . . .? But, no. He hadn’t even sent her a letter or a flower. It had been all on her side, and for that reason – I knew where she was bound for – I must stop her reaching him and humiliating herself.

I slipped the things into my pocket with some vague idea of using them to show her how childish she was being. She hadn’t taken her car. Gwendolen always disliked driving in central London. I took mine and drove to the tube station I knew she’d go to.

She came out a quarter of an hour after I got there, walking fast and glancing nervously to the right and left of her. When she saw me she gave a little gasp and stood stock-still.