Agatha Christie’s Use of Poisons In Her Books

As Agatha Christie wrote in her novel, They Do It With Mirrors, “Poison has a certain appeal. It has not the crudeness of the revolver bullet or the blunt weapon.”

If you’ve read some Agatha Christie novels, you’ve probably been introduced to various poisons that caused a murder. Christie seemed to have a major fascination with using poison as a way for murder. In fact, over 30 characters met their death with a poison in her works. This might lead you to wonder, where did her interest in this stem from?

During World War I, Agatha Christie once worked in a dispensary, which allowed her to learn about different poisons and see firsthand how they worked. In fact, she once stated that working in the dispensary inspired her to write a detective novel.

While working here may have prompted her to begin writing mystery novels, the dispensary also put her into contact with a pharmacist, who, while looking very calm and professional outwardly, became very enthusiastic when explaining the deadly effects of poison to her. A story has been told that this pharmacist would carry around curare in his pocket, which is deadly when it comes into contact with the bloodstream. He later told her he carried it around because he felt “powerful” doing so. This personality aspect perhaps inspired a few of her characters as well.

Besides naming some novels with poisons such as A is for Arsenic or Sparkling Cyanide, she used everything from hemlock to strychnine in her novels and created a unique plot around these toxins for that particular book. Her characters such as Miss. Marple, Hercule Poirot, and Tommy and Tuppence often come into contact with poisons during their investigations. Some of them are:

Used in The Caribbean Mystery, it causes symptoms such as blurry vision and hallucinations.


Found in Five Little Pigs, it affects the nervous system and causes the victim to become slowly paralyzed.


This was the first poison to make a debut in a Christie novel, which was featured in her first published book, The Mysterious Affair at Styles. It affects the CNS drastically and heavy muscle spasms occur.


Used in a quite a few of her books, such as Sparkling Cyanide, it stops the body from using oxygen, which kills the cells in the body and can lead to liver failure.


Featured in The Postern of Fate, this slows the heart rhythm and leads to the victim’s slow, eventual death.
While it may seem a little morbid and peculiar to be so fascinated with poisons and their effects, a mystery novel that properly puts them to use, can be very intriguing.

However, in some novels Christie may have describe the effects too meticulously. It was thought that her novel, The Pale Horse, introduced to the world the intricate, lethal use of thallium, which lead to murders, such as the ones Graham Frederick Young committed by mixing thallium in his co-workers tea. This however is not true, as thallium was introduced in a mystery novel many years before The Pale Horse was released.

Agatha Christie might not have been the first writer to introduce the use of poison in a mystery novel, but she is considered to be the novelist who wrote about them with such incredible detail, that a reader could learn about that new poison and its effects instantly.

Christie is known for her fantastic plots and well-developed characters, but her knowledge of chemistry and how she wrote such realistic descriptions of the toxin’s symptoms in her novels, is why she has been crowned “The Queen of Crime”.  It is with this writing brilliance and careful attention to detail, that her novels live on.


Photo credit: garryknight via / CC BY

Log In


Sign up for updates and we'll send you an exclusive story by one of our Edgar-nominated authors.