‘Walters went out and accosted the old idiot, wanting to know why he was hanging about there. He says it took him a good ten minutes to get anything intelligible out of the fellow. In the end he said, he supposed that Walters knew all about her — Walters said “Who?” — and this article said: “The sick lady”!

‘He’d found Shirley Johnson with a knife sticking out of her shoulderblades, and that was the nearest he could get to describing her!’

So Walters had followed the old man into the car park, which, ironically enough, adjoined Headquarters as well as the City Hall; and there, behind the dustbins in which the ancient had come to forage, he found that very sick lady lying stiff in the morning dew.

‘When you’re ready, if you like, I’ll take you round and show you the spot, but you’ll see how we found her in these photographs here. There wasn’t a lot of blood owing to the knife being left in, but we found one or two splashes leading from a spot about ten yards away.

‘He simply stabbed her, I imagine, and then lugged her over to the dustbins. As you see here, he chucked her handbag and coat down beside her. She wasn’t tampered with or mussed up and there were twenty pounds in her bag — likewise her driving licence, so we had no trouble in tracing her.’

Gently nodded, accepting the proffered bunch of glossy prints. They were interestingly gruesome, but not notably informative. The bins were standing by a terrace wall which flanked the large and much-used park, and though by day they offered little concealment, they would be effective enough after dark. The body had been carelessly dumped behind them. It had fallen on its face and had the right arm twisted beneath it. The thin handle of the paper knife protruded from below the left shoulderblade, and on it, in close up, one could read the inscription: ‘Pearson Cutlers, Sheffield, Eng.’ Only a small stain had appeared on the light-coloured dress.