Renfrew returns. He appears to be thoughtful, walks to the window, stares out into the gloom. It is almost dark now, though the snow retains a pallid glow and sends it up into his stern and thoughtful face.

“I saw a rider. Out by the school gates.” He turns to Charlie. “Someone to see Headmaster Trout, perhaps. But he did not enter the premises. Or is it someone looking for you, I wonder? A man with a dog.”

“Julius.”

Charlie mouths the name rather than saying it. All the same, Renfrew reads it off his lips.

“Mr. Spencer? Yes, I suppose it could have been him.” He scratches his chin. His fingers remain encased in gloves: a black hand in a white-blond beard. “Did you know he is Lady Naylor’s son from a previous marriage? Yes, I imagine she will have told you. A most unhappy association. I must confess I have my suspicions about the boy. His serenity feels artificial. Have you heard about sweets? They absorb Smoke at the moment of its genesis.” He frowns. “They will need to be banned entirely. Their present proliferation, even beyond the nobility — it is like building the kingdom of heaven out of cardboard.”

Renfrew steps over to the bed, slips his hands out of the gloves, folds them neatly on the night table. Charlie flinches when his teacher sits down at his bedside, but it is only to better see him. Renfrew has yet to light a candle. His face, in the failing light, is grave and marked by earnest concern. He might be sitting at Charlie’s sickbed, exhausted from the long hours of his vigil. Involuntarily, Charlie feels a pang of sympathy rise in him. Renfrew is following the commands of his conscience. It gives him no joy.

“I must ask you again, Mr. Cooper,” he says now, his own voice strained by thirst, “to pass on the information so vital for the future of our polity.

“Please, Charlie,” he adds, as gently as his dry tongue will allow, “put an end to this silly game.”

Charlie considers it. It is difficult to say whether his words would result in harm or in good. But he gave a promise. Not just to Lady Naylor but to Thomas. To Livia.

“I can’t.”

Renfrew nods.

“You do not lack in courage.”

He slips a hand into his coat pocket, pulls out a flask followed by what looks like a short, wide belt with a stiff piece of tubing sewn into its leather front.

“Don’t struggle now.”