The man with the umbrella emerges. He is followed by a monster. Four feet high and livid with the smells of the chamber pot, its hands cuffed to a belt. Where the face should be something else reigns, not quite a blank. Smooth, hairless skin, more black than brown: taut on top then hanging slack around the cheeks and neck. Twin lenses for eyes, palm-sized, ringed in metal. A leather trunk for a mouth, trailing to its chest.

A mask, Thomas realises. A child in a mask.

The man has attached a leash to his belt and walks the boy past them in precise, urgent steps. The child himself shuffles as though drugged; shoulders stooping; hopeless. They are past before Thomas can demand an explanation. All he can do is fall in step behind.

Up on deck the captain stands quietly near the stairwell. It is too dark to see his face. The man with the umbrella passes him a purse, then turns away without a word, marching the child across the plank. On the quay he stops, takes off his long woollen coat, and carefully wraps the child in it head to toe. The next moment he has gathered him up, is cradling the boy against his body: a shapeless mass, four feet long and sagging at the centre.

“Wait here,” the man orders, then walks briskly down the quay. After five steps he is no more than a shadow. After ten, he is lost in the night.

Lady Naylor rushes to the shelter of a tollbooth, beckons to them. Thomas hesitates. “I did not try to kill you,” she told them. Thomas finds that he believes her. Does that mean she is their friend? Her steps are hasty at any rate, the boot heels loud on the empty quay. She is nervous, it comes to Thomas. Impatient. Afraid. But perhaps he is simply projecting his own feelings, his heart too large in his chest, clenching, unclenching like a swollen fist.

Again she beckons, and still he remains out in the open, Livia by his side.

“So it’s all about this child,” he calls over, taking pleasure in the noise. “Where are you taking him?” Then it dawns on him. “The cage. The cage in your laboratory. It is meant for him.” He shudders. “I thought it was for me.”

“For you?” Her surprise seems genuine. “Yes, of course. It’s Renfrew’s fault. He told you that you had murder in your heart. He scared you, did he? And true enough, your Smoke has a certain quality. It is attuned to Julius’s in quite a startling manner. A phenomenon worthy of further study. Once upon a time I might have found a use for you.”

In the dark, across the distance, all he can see is the pale oval of her face. The eyes are deep pools, devoid of expression.