The chain of events which led to me leaving Ressonhurst Manor began one fine afternoon. I was bringing our heavy horse, Hercules, back from mowing when I came round the corner of the stable block. There were two horses, a chesnut and Lady Ryder's white mare, standing with side saddles on, ready for riding. I heard shouting from the stable and recognised Lord Ryder's voice. The stable door flew open and Lady Ryder ran out, with her husband in pursuit, brandishing a riding whip. A trickle of blood flowed down Lady Ryder's face and it didn't take much imagination to guess he'd hit her. I stood with Hercule's bridle in my hand, not knowing what to do.

Lord Ryder stopped and bellowed at me. "Get on with your work, Watson."

I led Hercules into the stable and heard no more but the incident bothered me. I'd heard the gossip in the kitchen, that Lord Ryder mistreated his wife but not seen any evidence before. I liked Lady Ryder. Often when I was working in the garden, she would stop to talk to me and admire the flowers. She was always polite and considerate. Lord Ryder, on the other hand, had never spoken a civil word to me. He might have been handsome, with his neatly cut brown hair and matching moustache, but there was a deep frown line between his eyes which gave him a bad-tempered look. Of course I knew the story. At the age of twenty two, he had wooed and wed the daughter of a friend of his father. The rumour said she was reluctant. But whatever Lord Ryder's grievances against his wife, I didn't think he should have hit her.

I'd worked at the Manor since I was a boy. Over time, I'd risen to be head gardener, with a little cottage which I shared with my wife and children. The garden was my pride and joy. It had extensive lawns, an orchard and a vegetable plot. The flower beds were arranged like spokes in a wheel, with roses in the centre.

Some weeks later, I was working on a bed of perennials, when Lady Ryder walked along the path with her friend Miss Cecilia Green. I lent on my spade, expecting Lady Ryder to greet me. It was easy to see why a young man's fancy might be drawn to her. She was beautiful, with dark hair and blue eyes, and her rose pink dress showed off her slim figure. Her friend, on the other hand, had drawn her hair back from her face and wore a plain brown dress, which made her look like a school teacher.

“The delphiniums are very fine,” Lady Ryder said.

I nodded at the clumps of tall blue and mauve flowers.“Thanks m'lady. They've done well this year.”

“Those  cream coloured flowers, are they monkshood? I thought they were usually blue.”

“They come in different colours. I chose these to go with the delphiniums.”

“Aren't they poisonous, though?”asked Miss Green. There was a sharpness about her tone I didn't much like.

“Yes Miss. You have to be careful how you handle them. I wouldn't grow them if there were little children around.” I glanced at Lady Ryder, wondering if I'd said the wrong thing. She was still childless after four years of marriage.

She gave a weak smile. “As it is, I don't suppose anyone is going to eat them.”

In the evenings, I often sat in the Manor kitchen, having a glass of ale with the groom. One evening, we were sitting chatting when one of the maids ran in, holding her skirts up with one hand. She stood trembling and pale.

“M'lord's been taken ill. I found him flat on the floor of the study. M'lady wants someone to fetch a doctor.”

The groom jumped to his feet. “I'll go. I'll take the fastest horse.”

For the next half hour, the household held its breath. The servants gathered in the kitchen, talking in low tones, as rumours began to circulate that Lord Ryder was dead. The doctor arrived and, some time afterwards, we were all summoned to the drawing room. We filed in, careful not to knock into any of the little ornaments that stood on occasional tables. In front of the heavy blue curtains stood the doctor, looking grave with his long face and grey whiskers. Lady Ryder was very pale, with her hair loose over an Oriental style dressing gown.

Her voice wavered as she spoke. “I am afraid that something terrible has happened. My dear husband is dead and, what is worse, Dr Grant here thinks he must have been poisoned.”

There were gasps from the assembled servants, until Lady Ryder held up her hand. “That doesn't necessarily mean someone meant to kill him. It could have been an accident. Tomorrow I will call a detective from London and he'll probably want to talk to you all. But I want everyone here to start thinking if you saw anything unusual or suspicious earlier today. It may be important.”

The next weeks were difficult. Servants who'd worked together for years looked at each other as if they were suspects. People whispered in corners. The detective, a Mr Stroud, arrived and interviewed us all separately in the study. When I went in and saw him sitting at the desk, I was surprised. I suppose I'd expected an educated gentleman but he looked more like a workman. He had a red face, ginger whiskers and hands crossed with scars.

“How long have you worked here, Mr Watson?” He had a distinct London accent.

“Thirty years, more or less.”

“Do you keep poisons to use in the garden?”

“Oh yes. I've got poison for rats and moles and poison for wasps.”

“Where do you keep them?”

I saw what he was driving at. “In a shed at the corner of the garden. I always keep it locked.”

“Have you noticed anything missing?”

I shook my head.

Nevertheless, he insisted on walking with me to the garden. He walked all round the shed, which was strongly built of seasoned timber, and examined the lock. The thought crossed my mind that he might be a reformed criminal and had built on that background in becoming a detective. I unlocked the shed and he examined my chemicals, which I kept in jars, all neatly labelled. It was a while before he was satisfied.

Nothing very definite came from the investigations. Lady Ryder dismissed her husband's valet, who was the last person who had seen him alive, but the accusation against him was of carelessness rather than anything worse. He had left glasses and trays of sweetmeats on tables, where someone could have tampered with them. Who that someone was remained a mystery.

Life returned to normal, but there were differences which soon caused gossip. The chief of these was the arrival of Miss Green. She'd visited before but now she stayed and the maids whispered she shared a bed with Lady Ryder. I dismissed such chatter and went on with my work as usual. Autumn had come, bringing the need to dig some plants out, cut others back and harvest apples and plums.

One morning, I was working among the perennials, cutting back the delphiniums, when I heard voices. Lady Ryder and Miss Green were walking along the path between the flower beds, holding hands. Suddenly, I remembered my conversation with them in the summer and stood dumbstruck. It all fitted. Lady Ryder and her friend had conspired to kill Lord Ryder, using poison from monkshood. They must have wanted him out of the way, so they could live together as lovers.

I went home and told my wife. My first thought was to alert the local Constabulary but, as we talked, I realised I was powerless to act. I had no evidence against Lady Ryder or Miss Green – just a hunch. And no-one would believe the word of a gardener against that of the lady of the manor.

I handed in my notice next day, saying something about the needs of my children. I was lucky enough to find a place with another noble family. However, I haven't much time for aristocrats these days. They may give themselves airs but they're no better than the rest of us. They may be worse.