The sergeant catches her out of a swoon and guides her to a chair that creaks as it takes her dead weight.

‘Dr Carfax told me you’d been seriously ill,’ he says with a gruffness that is very nearly concern. ‘I suppose he’s right. Should you be back home, miss?’

She shakes her head. ‘Cedric,’ she gasps.

‘Who?’

‘It’s my nephew. Sergeant, he has been taken. Abducted.’ She raises her chin, gulps in breath. ‘The killer was targeting me all along, I can prove that now.’

Were she not so wretched, she would triumph in the fact that she has finally managed to make the impassive sergeant blink.

‘I’d better fetch the Inspector.’ He stands, strides for the door and swings it open.

Simon is waiting there. Redmayne sighs. ‘I was wondering when you were going to show up.’

‘Where is she? Where is Miss Darken?’ Simon pushes inside, red and sweaty. When he sees her, he picks up her hands and clasps them in his own. ‘I have just this moment received your note.’

‘Oh Simon! They took him. Took him. Why would you not listen to me?’ For all her scolding, she is relieved to see him. Simon will take charge, he will make everything right, somehow. ‘Dr Carfax is the child’s father,’ she tells Sergeant Redmayne. ‘It was too late for letter carriers, so I sent him word by the first boy I could grab. I was not certain my message would get there.’

‘All right. Good. The Inspector will want to talk to both of you.’ He turns to leave, but Simon’s imperious voice arrests him on the threshold.

‘Wait!’ More softly, he adds, ‘A moment, Sergeant.’ He pats Agnes’s hands, returns them gently to her lap. ‘Alone, if you please.’

The policeman’s chest heaves beneath his uniform in another weary exhalation, but he gestures to the corridor, as if to say they may speak outside.

‘But Simon—’

‘I know, I know. Have no fear, Miss Darken, we shall return presently.’ He has regained his poise. Smoothing back his scanty hair, he follows Sergeant Redmayne and shuts the door behind him.

Once more, Agnes finds herself on the wrong side of the frosted glass.

It would be enough to vex any woman. What can they be speaking of, if she must not hear it? Vague mumbles reach her: a droning she recognises as the base note of Simon’s professional voice. Had she more strength, she would stand up and press her ear to the door.

She is Cedric’s real blood relation. She has spent more time attending to his welfare than either of his parents ever did; she has earned the right to be involved in this conversation.

A conversation that is apparently going to take a long time.