It wasn’t long before Quilley found what he was looking for. Beside ‘Oleander’ the note read, ‘See digitalis, 374.’ And there it was, set out in detail. Digitalis occurred in all parts of the common foxglove, which grew on waste ground and woodland slopes, and flowered from June to September. Acute poisoning would bring about death from ventricular fibrillation. No doctor would consider an autopsy if Peplow’s wife appeared to die of a heart attack, given her habits, especially if Peplow fed her a few smaller doses first to establish the symptoms.

Quilley set aside the book. It was already dark outside, and the downpour that the humid, cloudy day had been promising had just begun. Rain slapped against the asphalt roof tiles, gurgled down the drainpipe and pattered on the leaves of the overhanging trees. In the background, it hissed as it fell on the lake. Distant flashes of lightning and deep rumblings of thunder warned of the coming storm.

Happy with his solitude and his cleverness, Quilley linked his hands behind his head and leaned back in the chair. Out back, he heard the rustling of a small animal making its way through the undergrowth – a raccoon, perhaps, or even a skunk. When he closed his eyes, he pictured all the trees, shrubs and wild flowers around the cottage and marvelled at the deadly potential so many of them contained.

The sun blazed down on the back patio of the Madison, a small garden protected from the wind by high fences. Quilley wore his sunglasses and nursed a pint of Conner’s Ale. The place was packed. Skilled and pretty waitresses came and went, trays laden with baskets of chicken wings and golden pints of lager.

The two of them sat out of the way at a white table in a corner by the metal fire escape. A striped parasol offered some protection, but the sun was still too hot and too bright. Peplow’s wife must have given him hell about drinking the last time because today he had ordered only a Coke.

‘It was easy,’ Quilley said. ‘You could have done it yourself. The only setback was that foxgloves don’t grow wild here like they do in England. But you’re a gardener; you grow them.’

Peplow shook his head and smiled. ‘It’s the gift of clever people like yourself to make difficult things seem easy. I’m not particularly resourceful, Mr Quilley. Believe me, I wouldn’t have known where to start. I had no idea that such a book existed, but you did because of your art. Even if I had known, I’d hardly have dared buy it or take it out of the library for fear that someone would remember. But you’ve had your copy for years. A simple tool of the trade. No, Mr Quilley, please don’t underestimate your contribution. I was a desperate man. Now you’ve given me a chance at freedom. If there’s anything at all I can do for you, please don’t hesitate to say. I’d consider it an honour.’

‘This collection of yours,’ Quilley said. ‘What does it consist of?’

‘British and Canadian crime fiction, mostly. I don’t like to boast, but it’s a very good collection. Try me. Go on, just mention a name.’

‘E. C. R. Lorac.’

‘About twenty of the Inspector MacDonalds. First editions, mint condition.’

‘Anne Hocking?’

‘Everything but Night’s Candles.’

‘Trotton?’

Peplow raised his eyebrows. ‘Good Lord, that’s an obscure one. Do you know, you’re the first person I’ve come across who’s ever mentioned that.’

‘Do you have it?’

‘Oh, yes.’ Peplow smiled smugly. ‘X. J. Trotton, Signed in Blood, published 1942. It turned up in a pile of junk I bought at an auction some years ago. It’s rare, but not very valuable. Came out in Britain during the war and probably died an immediate death. It was his only book, as far as I can make out, and there is no biographical information. Perhaps it was a pseudonym for someone famous?’

Quilley shook his head. ‘I’m afraid I don’t know. Have you read it?’

‘Good Lord, no! I don’t read them. It could damage the spines. Many of them are fragile. Anything I want to read – like your books – I also buy in paperback.’

‘Mr Peplow,’ Quilley said slowly, ‘you asked if there was anything you could do for me. As a matter of fact, there is something you can give me for my services.’

‘Yes?’

‘The Trotton.’

Peplow frowned and pursed his thin lips. ‘Why on earth…?’

‘For my own collection, of course. I’m especially interested in the war period.’

Peplow smiled. ‘Ah! So that’s how you knew so much about them? I’d no idea you were a collector too.’

Quilley shrugged modestly. He could see Peplow struggling, visualizing the gap in his collection. But finally the poor man decided that the murder of his wife was more important to him than an obscure mystery novel. ‘Very well,’ he said gravely. ‘I’ll mail it to you.’

‘How can I be sure…?’

Peplow looked offended. ‘I’m a man of my word, Mr Quilley. A bargain is a bargain.’ He held out his hand. ‘Gentleman’s agreement.’

‘All right.’ Quilley believed him. ‘You’ll be in touch when it’s done?’

‘Yes. Perhaps a brief note in with the Trotton, if you can wait that long. Say two or three weeks?’

‘Fine. I’m in no hurry.’

Quilley hadn’t examined his motives since the first meeting, but he had realized, as he passed on the information and instructions, that it was the challenge he responded to more than anything else. For years he had been writing crime novels, and in providing Peplow with the means to kill his slatternly, overbearing wife, Quilley had derived some vicarious pleasure from the knowledge that he – Inspector Baldry’s creator – could bring off in real life what he had always been praised for doing in fiction.

Quilley also knew that there were no real detectives who possessed Baldry’s curious mixture of intellect and instinct. Most of them were thick plodders, and they would never realize that dull Mr Peplow had murdered his wife with a bunch of foxgloves, of all things. Nor would they ever know that the brains behind the whole affair had been none other than his, Dennis Quilley’s.

The two men drained their glasses and left together. The corner of Bloor and Spadina was busy with tourists and students lining up for charcoal-grilled hot dogs from the street vendor. Peplow turned towards the subway and Quilley wandered among the artsy crowd and the rollerbladers on Bloor Street West for a while, then he settled at an open-air cafe over a daiquiri and a slice of kiwi-fruit cheesecake to read the Globe and Mail.

Now, he thought as he sipped his drink and turned to the arts section, all he had to do was wait. One day soon a small package would arrive for him. Peplow would be free of his wife, and Quilley would be the proud owner of one of the few remaining copies of X. J. Trotton’s one and only mystery novel, Signed in Blood.

Three weeks passed and no package arrived. Occasionally, Quilley thought of Mr Peplow and wondered what had become of him. Perhaps he had lost his nerve after all. That wouldn’t be surprising. Quilley knew that he would have no way of finding out what had happened if Peplow chose not to contact him again. He didn’t know where the man lived or where he worked. He didn’t even know if Peplow was his real name. Still, he thought, it was best that way. No contact. Even the Trotton wasn’t worth being involved in a botched murder for.

Then, at ten o’clock one warm Tuesday morning in September, the doorbell chimed. Quilley looked at his watch and frowned. Too early for the postman. Sighing, he pressed the SAVE command on his PC and walked down to answer the door. A stranger stood there, an overweight woman in a yellow polka-dot dress with short sleeves and a low neck. She had piggy eyes set in a round face and dyed red hair that looked limp and lifeless after a cheap perm. She carried an imitation crocodile-skin handbag.