“Have you seen this man?” I asked him.

“It difficult to say . . .” He shook his head. “So many people pass through the square, it’s hard to . . .”

I pressed some coins into his hand and his demeanour changed at once. He leaned forward with a conspiratorial air: “He was being taken to the waterfront warehouses just east of here.”

“Thank you kindly for your help,” I told him.

“But hurry,” he said. “He was with Silas’s men. Such meetings tend to end poorly.”

Silas, I thought, as we weaved our way through the streets on our way to the warehouse district. Now, who was Silas?

The crowds had thinned considerably by the time we reached our destination, well away from the main thoroughfare, where a faint smell of fish seemed to hang over the day. The warehouse sat in a row of similar buildings, all of them huge and exuding a sense of erosion and disrepair, and I might have walked straight past if it hadn’t been for the guard who lounged outside the main doors. He sat on one barrel, his feet up on another, chewing, not as alert as he should have been, so that it was easy enough to stop Charles and pull him to the side of the building before we were spotted.

There was an entrance on the wall closest to us, and I checked it was unguarded before trying the door. Locked. From inside we heard the sounds of a struggle then an agonized scream. I’m not a gambling man, but I would have bet on the owner of that agonized scream: Benjamin Church. Charles and I looked at each other. We had to get in there, and fast. Craning around the side of the warehouse, I took another look at the guard, saw the telltale flash of a key ring at his waist, and knew what I had to do.

I waited until a man pushing a barrow had passed then, with a finger to my lips, told Charles to wait and emerged from cover, weaving a little as I came around to the front of the building, looking to all intents and purposes as though I’d had too much to drink.

Sitting on his barrel, the sentry looked sideways at me, his lip curled. He began to withdraw his sword from its sheath, showing a little of its gleaming blade. Staggering, I straightened, held up a hand to acknowledge the warning and made as though to move away, before stumbling a little and brushing into him.

“Oi!” he protested, and shoved me away, so hard that I lost my footing and fell into the street. I picked myself up and, with another wave of apology, was on my way.

What he didn’t know was that I left in possession of the key ring, which I had lifted from his waist. Back at the side of the warehouse we tried a couple of the keys before, to our great relief, finding one that opened the door. Wincing at every phantom creak and squeak, we eased it open then crept through, into the dark and damp-smelling warehouse.

Inside, we crouched by the door, slowly adjusting to our new surroundings: a vast space, most of it in darkness. Black, echoing hollows seemed to stretch back into infinity, the only light coming from three braziers that had been set out in the middle of the room. We saw, at last, the man we had been looking for, the man from the portrait: Dr. Benjamin Church. He sat tied to a chair, a guard on either side of him, one of his eyes purple and bruised, his head lolling and blood dripping steadily from a gashed lip to the dirty white scarf he wore.

Standing in front of him was a sharp-dressed man—Silas, no doubt—and a companion, who was sharpening a knife. The soft swooshing sound it made was almost gentle, hypnotic, and for a moment was the only noise in the room.

“Why must you always make things so difficult, Benjamin?” asked Silas, with an air of theatrical sadness. He had an English accent, I realized, and sounded highborn. He continued: “Merely provide me with recompense and all shall be forgiven.”

Benjamin regarded him with an injured but defiant gaze. “I’ll not pay for protection I don’t need,” he snapped back, undaunted.

Silas smiled and airily waved a hand around at the dank, wet and dirty warehouse. “Clearly, you do require protection, else we wouldn’t be here.”

Benjamin turned his head and spat a gobbet of blood, which slapped to the stone floor, then turned his eyes back to Silas, who wore a look as though Benjamin had passed wind at dinner. “How very gauche,” he said. “Now, what shall we do about our guest?”

The man sharpening the knives looked up. This was his cue. “Maybe I take his hands,” he rasped. “Put an end to ’is surgerin’? Maybe I take ’is tongue. Put an end to ’is wagglin? Or maybe I take ’is cock. Put an end to ’is fuckin’ us.”

A tremor seemed to go through the men, of disgust, fear and amusement. Silas reacted: “So many options, I can’t possibly decide.” He looked at the knifeman and pretended to be lost in indecision, then added, “Take all three.”

“Now hold on a moment,” said Benjamin quickly. “Perhaps I was hasty in refusing you earlier.”

“I’m so very sorry, Benjamin, but that door has closed,” said Silas sadly.

“Be reasonable . . .” started Benjamin, a pleading note in his voice.

Silas tilted his head to one side, and his eyebrows knitted together in false concern. “I rather think I was. But you took advantage of my generosity. I won’t be made a fool of a second time.”

The torturer moved forward, holding the point of the knife up to his own eyeball, bugging his eyes and grinning maniacally.

“I fear I lack the constitution to witness such barbarism,” said Silas, with the air of an easily offended old woman. “Come and find me when you’ve finished, Cutter.”

Silas went to leave as Benjamin Church screamed, “You’ll regret this, Silas! You hear me? I’ll have your head!”

At the door Silas stopped, turned and looked at him. “No,” he said with the beginnings of a giggle. “No, I rather think you won’t.”

Then Benjamin’s screams began as Cutter began his work, snickering slightly as he began to wield the knife like an artist making his first painterly strokes, as though at the outset of a much larger project. Poor old Dr. Church was the canvas and Cutter was painting his masterpiece.

I whispered to Charles what needed to be done, and he moved away, scuttling through the dark to the rear of the warehouse, where I saw him put a hand to his mouth to call, “Over here, y’ bastards,” then immediately move away, quick and silent.

Cutter’s head jerked up, and he waved the two guards over, glancing warily around the warehouse at the same time as his men drew their swords and moved carefully towards the back, where the noise had come from—even as there was another call, this time from a different pocket of blackness, an almost whispered, “Over here.”