No one else has braved the park. The lawns stretch pure as a freshly starched petticoat. There are no blemishes, no indication of where the footpaths and carriage drives lie buried. Agnes may choose her own route.

She sets off straight, towards the lake, hugging a belt of mature trees. The earth is uneven underfoot. Somewhere down there, life slumbers, waiting to burst forth again: green shoots, daffodils. They will be a long time coming. They have not even made it through October yet.

It is early, for snow, but then it has been a tumultuous year, what with the war breaking out and cholera in London over the summer. Everything is out of sorts. At least here there is beauty and peace.

Morpheus toddles on ahead, curly tail twitching. She watches him sniff and forage, following a pattern of twig-like bird tracks underneath the trees.

If she is reasonable – and she tries to be – she can understand why Simon grew prickly at the mention of Montague. His objections against the man are probably just. Her own should be stronger. But the difference is, she forgives him. If that makes her despicable as a woman – well, she would rather be happy than prudent.

Let her assume Simon is right: the drowned man is somebody else entirely. It hardly makes circumstances much better. She is still faced with the question: why are her sitters dying?

Agnes regards the humped shapes of box, laurel and privet hedges. They look like furniture covered by dust sheets, or perhaps ghosts in their shrouds. Her mind returns to that strange, vibrant young woman in Walcot Street and her outlandish claims of seeing auras. What colour did she say Agnes’s was? Ash of roses. She imagines the pink seeping out from the bottom of her skirts into the snow, a circle spreading to reach Morpheus who is digging beneath the trees. It must be interesting for Miss West to see everyone like that: tinged with their own hue. Agnes views them in lines of black and white.

You should talk to the Sylph. Just to know for sure.

It might be that Miss West’s sister could contact the dead and tell Agnes what happened to her clients. But even if Spiritualism is real, it is wicked, a kind of devilry that should not be meddled with. She knows this. She tries to remind herself.

A pigeon breaks free of a group of conifers and takes wing.

When all is said and done, Agnes should trust Simon. Accept that both deaths were unfortunate mischances and no incidents like them will ever occur again.

Morpheus barks.

It is odd, because Morpheus is not usually a barking dog; he vocalises through grunts instead. Yet here he is, yowling over and over in distress. His paws scrabble wildly, flinging up powdery snow.

Agnes doesn’t know what she is supposed to do.

‘Bad dog,’ she tries. ‘Come here!’

He starts to obey but then dashes back yapping.