Dr Raven had confessed the depth of his fears. He kept observing the wound, and told me that the paucity of pus concerned him. He would have expected far more. His deduction was that it had gathered somewhere inside her, from where there was no possibility of draining it. I knew from experience that, had infection taken hold, death would be a matter of course.

Earlier in the day, a policeman had come to the door enquiring as to Dr Raven’s whereabouts. As the hours passed and still he did not reappear, I suspected something had befallen him, and I hoped it had not been before he discovered the confession that would liberate me. I had gone to great trouble and did not wish my efforts to be in vain.

I had long ago learned the importance of putting plans in place should I fear discovery, and how drastic such action might have to be. But what better way to deal with suspicion than to give the suspicious exactly what they were looking for? I would be sorry to lose my own name, but I had lost it once before, when I was taken into the Dempster household.

It was harder to give up all that came with my reputation. That said, I had already begun telling people Martha was a nurse too. I even had my first client, though I would not charge Dr Raven for my services. I did not intend for him to survive long enough to pay me. He had recognised my hand once, so I could not risk him doing so a second time, and I certainly had no intention of stopping. With him and Mrs Banks dead, I could indulge my appetites as freely as before.

Dr Raven would take his own life in despair at the loss of a woman he clearly loved. I would tell people that I believed he blamed himself for her death following the dangerous procedure he had carried out, against the wider wisdom of his peers.

And at a stroke I would be free of the only two people who had ever suspected me.

SEVENTY-THREE

aven felt a strangling helplessness as he watched darkness begin to fall through the small windows high on the wall on the other side of the bars. Sarah was out there in the night, at the mercy of a murderess who had wiped out whole families.

At least he no longer had to worry about his personal safety. As Gregor predicted, McLevy had called for him some time ago, and though Raven could not now draw upon his physical protection, no one dared molest him, for it was clear that he and the giant were in league.

He saw movement at the door and looked up, as he had done every time it opened, his automatic response an uncomfortable mixture of impatience and dread. At such time, it feels like the not knowing is the worst part, until certainty shows you otherwise.