The best-selling fiction author of all time according to Guinness World Record lists, Agatha Christie is best known for her 66 detective novels, 14 short story collections, her iconic sleuths Hercule Poirot and Miss Marple, and the world’s longest-running play, The Mousetrap. Less well known is the fact that she was a member of the pharmacy profession.

However, the clues that point to her pharmaceutical knowledge are there in her stories. Her novels are filled with multiple murders, where often the victims – spoiler alert – have been exposed to deadly poisons.

This fascination with murder by poison could be said to date back to the time Agatha spent working as an apothecary’s assistant and dispenser during the First World War.

Writing in her autobiography about her first novel, written in 1916, The Mysterious Affair at Styles, Agatha says: “Since I was surrounded by poisons, perhaps it was natural that death by poisoning should be the method I selected.”

As per agathachristie.com, “the murderer’s use of poison was so well described that when the book was eventually published Agatha received an unprecedented honour for a writer of fiction" – namely, being reviewed by a publication for pharmacists.

 

Early life

 

The pharmacy-educated writer’s love of fiction began at an early age. Agatha Mary Clarissa Miller was born on 15 September 1890 in Torquay, Devon. By the age of five, she had already taught herself to read.

According to agathachristie.com: “She absorbed the children’s stories of the time – Edith Nesbit (The Story of the Treasure Seekers, The Railway Children) and Louisa M Alcott (Little Women) but also poetry and startling thrillers from America.”

Agatha “invented imaginary friends, played with her animals, attended dance classes and began writing poems when she was still a child”, the website says.

At the age of 11, her father died after a series of heart attacks, and she became her mother’s closest companion. In her late teens, she studied to be a classical musician in Paris but was too nervous to perform. By the age of 18, she was writing short stories.

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In 1912, Agatha met Archibald “Archie” Christie, a Royal Artillery Officer and qualified aviator, who was seconded to the Royal Flying Corps in April 1913.

By the time they married on Christmas Eve 1914, both had experienced war – Archie in France and Agatha through her work with the Voluntary Aid Detachment of the Red Cross. 

As a nurse, she cared for the seriously wounded, assisted in operations and cleaned up after amputations, from October 1914 to May 1915 at Torquay’s Town Hall Red Cross Hospital and then from June 1916 to September 1918.

 

Apothecary's assistant and dispenser

 

In 1915, Agatha joined Torquay’s Red Cross Hospital pharmacy, where she trained as an apothecary’s assistant, which involved learning both theoretical and practical aspects of chemistry.

It was during this training that she acquired her knowledge of poisons. On 13 April 1917, she completed the examination of the Society of Apothecaries in London. Agatha made up prescriptions, which was an extremely skilled job at a time when pills, tonics and lotions were made by hand. By the end of the war, Agatha was a dispenser.

It has been suggested that Agatha experienced anxiety during her time working in the hospital dispensary, and that her worries propelled her to become a writer.

According to agathachristie.com “it was probably her own dread of making a mistake when handling potentially deadly chemicals in the pharmacy that made Christie start writing about poisoning.

“Her anxiety once forced her to get out of bed and go back to the hospital in the middle of the night to check that she had not accidentally put the lid she had been using to hold carbolic acid back onto an ointment jar.”

During her time at the Torquay pharmacy, Agatha realised a chemist had made a mistake in his calculations and put too much of a potentially dangerous drug into a batch of suppositories, agathachristie.com confirms.

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Knowing that he wouldn't like to be corrected, Agatha instead knocked the much-too-strong medicine to the ground and stomped on them to make them unusable. The chemist was to inspire a character in her book The Pale Horse.

As a writer, Agatha first drew on her knowledge of poisons in her debut novel The Mysterious Affair at Styles, which introduced one of her most famous characters, Hercule Poirot. Published in 1920, the novel centres on the death of a woman by strychnine poisoning. And like Agatha, another character in the book also works at a hospital pharmacy during the war.

After the war, Agatha gave birth to her only daughter, Rosalind, in 1919. She continued to write – experimenting with different types of thriller and murder mystery stories, and creating another of her famous sleuths, Miss Marple.

The 1920s saw the death of her mother, and the breakdown of her first marriage. She was divorced in 1928.

 

Second World War

 

But she continued to be a prolific writer, typically producing two to three books a year. She was also well-travelled, which included spending time in the Middle East with her second husband, archaeologist Sir Max Mallowan, who she met on an archaeological dig and married in 1930.

During the Second World War, Max got a wartime job in Cairo, where he used his knowledge of languages to assist the war effort. Meanwhile, Agatha stayed in England and returned to pharmacy, volunteering at the dispensary at University College Hospital in London.

During that time, she also managed to fit in writing such classics as And Then There Were None, The Body in the Library, and The Moving Finger.

She continued to bump off her fictional victims with poison. Cyanide was a favourite, but toxic plants such as hemlock and foxglove and unusual chemicals such as thallium and ricin were also used to kill off her characters.

After the war, Agatha enjoyed a slower pace of life. But she continued to write, and also became involved in theatrical productions of her work.

According to agathachristie.com, Agatha’s dislikes included: “Crowds, being jammed up against people, loud voices, noise, protracted talking, parties, and especially cocktail parties.”

In addition, it says, she disliked “cigarette smoke and smoking generally, any kind of drink except in cooking, marmalade, oysters, lukewarm food, grey skies, the feet of birds, or indeed the feel of a bird altogether”.

Her final and fiercest dislike was “the taste and smell of hot milk”.

However, agathachristie.com notes that she enjoyed: “Sunshine, apples, almost any kind of music, railway trains, numerical puzzles and anything to do with numbers”.

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The website notes that she also enjoyed “going to the sea, bathing and swimming, silence, sleeping, dreaming, eating, the smell of coffee, lilies of the valley, most dogs, and going to the theatre”.

Agatha's last public appearance was at the opening night of the 1974 film version of Murder on the Orient Express, starring Albert Finney as Hercule Poirot. Agathachristie.com reports that, in her view, the film was “a good adaptation with the minor point that Poirot's moustaches weren't luxurious enough.”

After a hugely successful writing career that spanned five decades, Agatha died peacefully on 12 January 1976.

However, her memory lives on through her novels, which are frequently translated onto the big and small screens.

These classic and enduring tales of murder by poison owe much to the pharmaceutical knowledge Agatha gained in the hospital dispensary during wartime.