‘It is hardly Pearl’s doing,’ she points out and knocks at the door.

There is no answer.

The rain intensifies, running out of the eaves in great torrents. Agnes knocks again and again.

‘Pearl,’ she calls. ‘Pearl, it’s me. Agnes. Do not be afraid, dear. I have brought the doctor.’

‘Perhaps she does not wish to see us,’ Simon surmises.

‘She is afraid of her sister,’ Agnes corrects him, knocking until her knuckles hurt. ‘Either that or … Oh, Simon, you do not suppose Miss West has beaten the child? Perhaps she cannot answer the door.’

Simon bites his lip. The crowd on the pavement has thinned; even the street sellers are seeking cover now. He glances around, then hands Agnes his medicines. She takes them awkwardly, juggling the umbrella.

‘Stand back.’

Raising a foot, he kicks open the door.

It is a cheap thing with a paltry lock but all the same, Agnes is surprised by how quickly it yields. She hears a gasp from inside as the door bangs back against the inner wall.

No one on the street remarks or cares.

‘After you, Miss Darken.’

She passes him the umbrella to disassemble and enters the house, where acrid fumes replace the damp street smells. If she had her hands free, she would pull out her handkerchief and cover her nose.

Her vision takes a moment to adjust to the unnatural gloom; it is only when Simon closes the front door and squelches in after her that she discerns Pearl, hovering at the end of the hallway with all the fragility of a moth.

Her pinched face is wary, unsure.

Agnes cannot make out any bruises, but the child does look ill-conditioned. Her once alabaster skin appears jaundiced and her wrists look thin enough to snap.

An arrow of guilt quivers in Agnes’s heart.

‘Look, dear,’ she croons, holding up Simon’s purchases. ‘We have brought medicine.’

The girl regards them the same way Agnes inspected the cabinet and the crystal ball on her first visit.

‘You’re … not meant to be here,’ Pearl croaks at last.

Simon comes forward, past Agnes, but still leaving a comfortable distance between himself and the girl. Puffing, he bends down to her height. If he is surprised to see an albino child, he does not show it.

‘Forgive the intrusion, Miss …’

‘Meers.’

‘Miss Meers. My name is Dr Carfax. I understand that your father is very unwell and I should like to help him, if I can.’

Pearl looks at her feet, scuffs one against the floor. The struggle is plain on her face. The poor child wants to trust Simon, but all her education – or rather her indoctrination – tells her not to.

‘Myrtle says your medicine’s poison.’