Adding a Touch of Suspense by Slipping Some Poison in the Cup

Want to up the suspense of your medieval novel or short story? There’s nothing like a drop or two of poison in a character’s wine to make a reader sit up and take notice.

But where do we go to find information about medieval poisons?

An excellent starting point is Deadly Doses: A Writer’s Guide to Poisons, by Serita Deborah Stevens with Anne Klarner. Deadly Doses is part of the Howdunit Series published by Writers Digest Books.

Now, this book is not strictly about “medieval” poisons, so you must do a little searching to find an appropriate poison for your time period. But of the eleven chapters, several can be quickly eliminated from your search: “Houshold Poisons”, “Medical Poisons”, “Pesticides”, “Industrial Poisons”, and “Street Drugs” all belong to a more modern age, so there’s no need to waste precious research time on those sections.

That leaves “Poisonous Plants”, “Fragile Fungi”, and “Snakes, Spiders, and Other Living Things” as topics to explore.

For my novel, Loyalty’s Web, I found myself leaning towards some use of a poisonous plant. After a short chapter introduction, the chapter breaks down into the following poison subsections: “Quickly Fatal”; “Mistaken for Edible or Eaten by Mistake”; “Edible in Small Quantities, Certain Parts Edible, or Edible Certain Times of the Year”; “Flowering Plants”; and “Miscellaneous Plant Poisons”.

Each of these subsections is further broken down in the following super-sub categories:

“Name”, “Toxicity”, “Location”, “Deadly Parts”, “Effects and Symptoms”, “Reaction Time”, “Antidotes and Treatments”, and “Notes”.

The first thing I did was take a red pencil and mark the name of each plant under the “Location” category, that was listed as “native to Europe, Britain or England” or that may have been brought there by the Romans. The important thing is to be sure that whatever poison you choose was actually available to the people of the Middle Ages in the area of Europe that you are writing about. (I’ll talk about backup sources in my next post.)

Once you’ve whittled the possibilities down with a red pencil or other highlighter, you can focus your research on the additional information for each of the poisons you’ve marked, and gradually come to a decision about which poison will best serve the plot of your story.

Since I wanted to keep my readers guessing a bit about the poison angle at the beginning, I decided to go with a plant that could be “Mistaken for Edible or Eaten by Mistake”. I eventually settled on water hemlock, also known as cowbane. Although the “Location” information seemed to place water hemlock mostly in North America, a note in the first chapter to Deadly Doses, “A Short History of the Dreaded Art”, informed me that : “Water hemlock, foxglove, henbane, and the prussic acid of the almond tree were all found in the Parisian woods and meadows.” (Deadly Doses, p 6) This told me that the plant I wanted also grew in France (the location of Loyalty’s Web). It also taught me that it can be well worth your while to read “generalized” chapters about the background of your subject, before moving on to seemingly more pertinent “specialized” chapters. Valuable tips and facts are often “hidden” in Introductions and the like.

Once I’d settled on water hemlock, which I referred to by its nickname, cowbane, throughout my novel, I went on to glean the following information from its entry:

It had a toxicity level of 6, placing it in the “supertoxic” category, meaning that only a very, very small amount of the poison would cause death. I also learned that younger plants, growing in the springtime, are more poisonous, which again fit with the springtime setting of my novel.

Under “Deadly Parts”, I learned that although the entire plant is poisonous, most of the poison is contained in the roots and rootstock. So when I finally had a character uncover the “source” of the poison, I had her discover a portion of cowbane root that someone in the castle had been hiding. (Don’t want to give too much away here by telling you who!) The poison was also dissoluble in alcohol, which made it perfect for adding a few drops to a cup of wine.

Although it never went that far in my novel, if my hero had actually drunk his tainted cup of wine, this would have been the effect: “Restlessness and feelings of anxiety, pain in the stomach, nausea, violent vomiting, diarrhea, dilated pupils, labored breathing, sometimes frothing at the mouth, weak and rapid pulse, and violent convulsions terminated by death. Respiratory failure is the cause of death.” (Deadly Doses, p 61)

Death would occur between 20 minutes to an hour. (Given the process leading up to death, I think I’d rather go fast, than slow!)

There are antidotes and treatments, but most of them belong to a more modern age, and if the source of the poison had been concealed in something like wine, one would not have known what sort of antidote to try in the first place. Besides which, given the potentially fast-acting nature of the poison, a character would have to be very self-possessed, knoweldgable, and/or experienced to gather one’s wits quickly enough to act in time to save the victim.

This is just a single example of the kinds of valuable, detailed information available in Deadly Doses. As a starting point for authors of mystery, suspense, or who just like to throw in a bit of “surprise” to keep their readers guessing, I highly recommend Deadly Doses, by Serita Deborah Stevens and Anne Klarner.

This post has run on long enough, so I’ll stop here. Next time, I’ll share with you my “backup sources” and more on medieval plants.

Note: Deadly Doses is widely available in Used Books on Amazon.com. Writer’s Digest Books lists the title Howdunit: Book Of Poisons, by Serita Stevens and Anne Louise Bannon, which may well be the same as Deadly Doses with a new name, but not having a copy of my own, I can’t vouch for that. The description sounds very similar, and since my copy of Deadly Doses is 298 pages, and Book of Poisons lists at 368 pages, I’m guessing that Book of Poisons may merely be an updated version of Deadly Doses, with a new title. If so, this is definitely a book you will want to consider including in your library!