‘Only if I have to,’ he says. ‘I hope she will stay willingly, but she might not. I hope she will be enticed and will find the idea of being my plaything quite entertaining. But if she does not, that is our problem, not yours. So don’t worry about that side of things. Instead tell me: is this not the most luxurious room in the whole of Edinburgh town? There is a drawer for her rouges and another for sweetmeats – she has a tooth for candied fruits – and somewhere she can keep her laudanum to hand. She can have all the laudanum she needs here – tell her that. And I have purchased a set of dominoes too, best bone and ivory.’

I have been more terrified in my life, but not often.

‘You do not mean to let her escape, do you?’ I say. ‘You will keep her here until you tire of her and then she will likely end up overdosed on laudanum.’

He pretends not to hear me, and leaps from the room back into the parlour and paces the Turkish carpet. I follow him, desperate to be out of that chamber.

‘Now I shall give you Mrs Rose’s address, and clear directions, so there’s no danger of you getting lost. But do not go to her lodgings. There is a coffee house she frequents after dark. It is where she plies her trade. Go there and simply bump into her. And this is what you are to tell her.’

He pauses here, his eyes roaming the ceiling, the window, the floor.

‘Tell her you forgive her the theft. Tell her that you are delivered. From death. And that in the afterlife you had a vision, and that you are to forgive all those who have sinned against you, like in the Lord’s Prayer. Tell her that you have a fine place where you are living now – from your earnings – and invite her to take tea with you. Two old pals from Kelso, finding their way in the big town. Then you are to bring her to this apartment. Not the gin shop. Tell her that is where you work, if she asks, for she might have heard tales of you and we do not want to scare her off. But do not take her to the gin shop. Instead, bring her here. And when she is safely in this parlour, taking her tea, you will excuse yourself and leave.’

‘And you will be here, I suppose?’

‘I will await you leaving. Then I will announce myself to her. When you leave, make sure the door is closed and lock it behind you. I will give you a key so that you can get in, so use that. I will put some powders by the tea leaves and you can put some in her cup. It will make her sleepy.’