The bell push was obviously electronic, the sound echoing melodiously inside, and after a while the door was opened by a pleasant-faced young maid in a nylon working overall.

‘Yes, sir?’ she said to Miller.

‘Is Mr Craig at home by any chance?’

‘Colonel Craig,’ she said in a tone of mild reproof, ‘is in London at the moment, but we’re expecting him home tonight.’

‘Who is it, Jenny?’ a voice called and then a young woman appeared from a door to the right.

‘The gentlemen wanted to see the Colonel, but I’ve told them he isn’t at home,’ the maid said.

‘All right, Jenny, I’ll handle it.’ She came forward, an open book in one hand. ‘I’m Harriet Craig. Is there anything I can do?’

She was perhaps twenty-two or -three and nothing like her sister. The black shoulder-length hair framed a face that was too angular for beauty, the mouth so wide that it was almost ugly. And then, for no accountable reason, she smiled and the transformation was so complete that she might have been a different person.

Miller produced his warrant card. ‘I wonder if we could have a word with you, Miss Craig?’

She looked at the card and frowned. ‘Is anything wrong?’

‘If we could go inside, miss,’ Brady said gently.

The drawing room into which she led them was beautifully furnished in excellent taste and purple and white hyacinths made a brave splash of colour in a pewter bowl that stood on the grand piano. She turned, a hand on the mantelshelf.

‘Won’t you sit down?’

Miller shook his head. ‘I think it might be a good idea if you did.’

She stiffened slightly. ‘You’ve got bad news for me, is that it?’ And then as if by intuition, ‘Is it my sister? Is it Joanna?’

Miller produced one of the photos from his inside pocket. ‘Is this her?’

She took the photo from him almost mechanically and her eyes widened in horror. When she spoke, it was in a whisper. ‘She’s dead, isn’t she?’

‘I’m afraid so,’ Miller said gently. ‘She was taken out of the river at dawn today. To the best of our knowledge, she committed suicide.’

‘Suicide? Oh, my God.’

And then she seemed to crack, to break into a thousand fragments and as Miller’s arms opened to her, she lurched into them, burying her face against his chest like some small child seeking comfort and strength in a world she could no longer understand.

Jack Palmer lifted the sheet and for a brief moment Harriet Craig looked down on the dead face of her sister. She swayed slightly and Miller’s grip tightened on her elbow.

‘All right to use your office for ten minutes, Jack?’

‘Help yourself.’