HAVING DECIDED TO DO the hard detective work related to the murder of Edmond Dickenson myself, I set about it with a will the next morning. Fortifying myself with two-and-a-half cups of laudanum (about two hundred minims, if one were applying the medicine drop-by-drop), I took the mid-day train to Chatham and hired a cart to whisk me—although “plod me” would be a better choice of verb given the age and indifference of both the horse and cart-driver—to Gad’s Hill Place.

As I approached the important interview with Dickens, I began to see more clearly the to-this-point-amorphous idea of my fictional detective in The Eye of the Serpent (or perhaps The Serpent’s Eye), Sergeant Cuff. Rather than the brusque, stolid, and gruff Inspector Bucket of Dickens’s Bleak House—an unimaginative character in the most literal sense, I thought, since he was based so clearly on the younger version of the actual Inspector Field—my Sergeant Cuff would be tall, thin, older, ascetic, and rational. More than anything else, rational, as if addicted to ratiocination. I also imagined my ascetic, grey-haired, hatchet-faced, ratiocinated, pale-eyed and clear-eyed Sergeant Cuff as nearing retirement. He would be looking forward, I realised, to devoting his post-detective life to beekeeping. No, not beekeeping—too odd, too eccentric, and too difficult for me to research. Perhaps— growing roses. That was the ticket… roses. I knew something about roses and their care and breeding. Sergeant Cuff would know… everything about roses.

Most detectives begin with the murder and spend ages following roundabout clues to the murderer, but Sergeant Cuff and I would invert the process by starting with the murderer and then seeking out the corpse.

“My dear Wilkie, what a pleasant surprise! The pleasure of your company two days in a row!” cried Dickens as I approached the house and he came out, tugging on a wool cape-coat against the chill wind. “You’re staying for the rest of the weekend, I trust.”

“No, just stopping by for a quick word with you, Charles,” I said. His welcoming smile was so obviously sincere in his childlike way—a little boy whose playmate has shown up unexpectedly—that I had to return the smile, even though inside I was holding fast to the cool, neutral expression of Sergeant Cuff.

“Wonderful! I’ve just finished my morning’s work on the last of the introductions and my Christmas story and was about to set out on my walk. Join me, dear friend!”

The thought of a twelve- or twenty-mile hike at Charles Dickens’s pace on this windy, snow-threatening November day caused a headache to start its throbbing behind my right eye. “I wish I could, my dear Dickens. But as you mentioned Christmas… well, that was one of the things that I wished to talk to you about.”

“Really?” He paused. “You—the original ‘Bah! Humbug!’ Wilkie Collins—interested in Christmas?” he said and threw back his head for a true Dickens laugh. “Well, now I can say that I have lived long enough to see all improbabilities come to pass.”

I forced another smile. “I was just wondering if you were having one of your usual galas this year. The day is not too far distant, you know.”

“No, no, no, it isn’t,” said Dickens. Suddenly he was calmly and coolly appraising me. “And no, no gala this year, I fear. The new round of readings begins in early December, you may recall.”

“Ah, yes.”

“I shall be home for a day or two for Christmas itself,” said Dickens, “and of course you shall be invited. But it shall be a modest affair this year, I’m sorry to tell you, my dear Wilkie.”

“No worry, no worry,” I said hurriedly, improvising my little scene in a way that I felt would do justice to the yet-to-be-created Sergeant Cuff. “I was just curious… will you be inviting Macready this year?”

“Macready? No, I think not. I believe his wife is indisposed this season anyway. And Macready travels less and less these days, you remember, Wilkie.”

“Of course. And Dickenson?”

“Who?”

Aha! I thought. Charles Dickens, the Inimitable, the novelist, the man with the iron memory, would not, could not, ever forget the name of the young man whom he’d saved at Staplehurst. This was a murderer’s—or soon-to-be-murderer’s—dissembling!

“Dickenson,” I said. “Edmond. Surely you remember last Christmas, Charles! The somnambulist!”

“Oh, of course, of course,” said Dickens even while he waved away the name and the memory. “No. We shan’t be inviting young Edmond this Christmas. Just family this year. And the closest friends.”

“Really?” I feigned surprise. “I thought that you and young Dickenson were rather close.”

“Not at all,” said Dickens while he pulled on his expensive and far-too-thin-for-such-a-day kid gloves. “I merely looked in on the young man from time to time during his first months of recovery. He was, you remember, Wilkie, an orphan.”

“Ah, yes,” I said, as if I could have forgotten this essential clue as to why Dickens had chosen him as his murder victim. “Actually, I had rather looked forward to chatting with young Dickenson on a couple of topics we were discussing last Christmas. Do you remember his address by any chance, Charles?”

Now he was looking at me most queerly. “You wish to pick up a conversation you were having with Edmond Dickenson almost a year ago?”

“Yes,” I said in what I hoped was my most authoritative Sergeant Cuff manner.

Dickens shrugged. “I’m quite sure I don’t remember his address, if I ever knew it. Actually, I believe he moved around quite a bit… restless young bachelor, always changing quarters and so forth.”

“Hmmm,” I said. I was squinting against the cold wind out of the north that was rustling Dickens’s winter-pruned hedges and driving the last of the sere leaves from the trees in his front yard, but I might as well have been squinting through the suspicion I felt.

“In fact,” Dickens said brightly, “I believe I remember young Dickenson left England last summer or autumn. To go make his fortune in southern France. Or South Africa. Or Australia. Some promising place like that.”

He’s playing with me, I thought with an electric surge of Sergeant Cuff—ish certainty. But he does not know that I am playing with him.

“Too bad,” I said. “I would have enjoyed seeing young Edmond again. But there’s nothing for it.”

“There isn’t,” agreed Dickens, his voice muffled by the thick red scarf he’d pulled up over his lower face. “Are you sure you won’t join me for the walk? It’s a perfect day for it.”

“Another day,” I said and shook his hand. “My cart and driver are waiting.”

But I waited until the writer was out of sight and the tap of his stick out of earshot and then I rapped at the door, handed my hat and scarf to the servant who answered, and went quickly to the kitchen, where Georgina Hogarth was seated at the servants’ table going over menus.

“Mr Wilkie, what a pleasant surprise!”

“Halloo, Georgina, halloo,” I said affably. I wondered if I should have wore a disguise. Detectives often wore disguises. I’m sure that Sergeant Cuff did upon occasion, despite his uniquely tall and ascetic appearance. Sergeant Cuff was almost certainly a master of disguises. But then, that ageing Scotland Yard detective did not suffer the handicaps of my disguise-proof shortness, full beard, receding hairline, weak eyes that demanded spectacles, and oversized, bulbous forehead.

“Georgina,” I said easily, “I just ran into Charles on his way off to his walk and popped in because my friends and I are planning a small dinner party—a few artists and literary people—and I thought that young Dickenson might enjoy such an evening. But we don’t have his address.”

“Young Dickenson?” Her expression was blank. Was she an accomplice? “Oh,” she said, “you mean that boring young gentleman who sleepwalked here Christmas Day night last.”