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  • Marthe Jocelyn

“Give Me a Decent Bottle of Poison”: Writing a Mystery

My most recent book is a middle-grade mystery, my first. I realized, after only a few days of struggling to construct a murder, that I didn’t know how to do it. I’d written plenty of novels, but I’d always begun with a person, not the plot.

The person, in this case, was given to me by my editor Tara Walker, at Tundra Books. “What do you think of Agatha Christie as a twelve-year-old sleuth?” she said.

I liked the idea a lot. This was familiar territory. Conceiving an elaborate puzzle became secondary to imagining the character who would follow the clues and catch the villain — and so much more besides. My Aggie is a girl with a Morbid Preoccupation who is grieving for her deceased Papa, making an unusual friend, and learning a little about becoming a writer. The mystery elements were all there in the background: a poisoned corpse and a gruff detective inspector, a list of suspects and a couple of red herrings, an anonymous letter, a mistaken identity, and someone in disguise. But the girl comes first.

I discovered after a tremendous amount of reading — Agatha Christie’s autobiography, three biographies, an edited collection of her notebooks, and probably fifty of her novels and short-story collections — that Christie took an opposite approach.

The titular character in her short story “Mr. Eastwood’s Adventure” is a writer with the opinion that “the two essentials for a story were a title and a plot — the rest was mere spadework. Sometimes the title led to a plot all by itself, as it were, and then all was plain sailing…” This seems to be how Christie felt herself. She is more admired for her impeccable riddles than for the depth of her characters. But, as is clear from her notebooks, she often did not know who her killer would be when she began a book, nor the identity of the victim. “Who is killed?” she asks herself when sketching out Ordeal by Innocence. “Philip poisoned — doesn’t hold up, or Tina stabbed?” She frequently drew maps to clarify the geographical mechanics of a murder, especially if timing was tight. She listed murderous variations until settling on the one that clicked.

In Christie’s The Third Girl, the character of Ariadne Oliver, a crime novelist, spills a similar list of possibilities to Hercule Poirot when a young woman appeals for help after being drugged, believing she might have killed someone:

She could have run over someone in her car and not stopped. She could have been assaulted by a man on a cliff and struggled with him and managed to push him over. She could have given someone the wrong medicine by mistake…She could have come to and found she had stabbed someone…

The treasure trove of Christie’s wildly disorganized notebooks, seventy-three still in existence, also reveals that she jotted down dozens of plot points or ideas for murders, sometimes repeating the same ones over a period of years. Twins, self-engineered kidnappings, mirrors, and chambermaids make multiple appearances. “Stabbed through the eye with hat pin” is noted four times, and Poirot forced to regrow his mustache after an accident with a flame is mentioned twice, though never used. Also never used was the idea behind this scrawl: “Nitro benzine — point is — it sinks to bottom of glass — woman takes sip from it — then gives it to husband.”

Her character “studies” are brief sketches: thin-blooded people not driving the action or adding emotional depth but created to fit into her scheme, as on this list for Hercule Poirot’s Christmas:

A family such as Arthur — the good stay at home one Lydia — clever nervy wife Mervyn — son still at home dilettante artist Hilda — his very young wife — rather common David — very mean — sensitive Dorothy — his articulate wife Regina — unhappy woman — separated from husband Caroline — her daughter — fascinating — reportedly bad Edward — her devoted husband — bad lot

In the published version, these characters are substituted, combined, or deleted — as the plot requires.

Devising what the plot required was Christie’s genius, but even that she kept mostly inside her head. Her notes are dashed, only useful to an outside reader who is familiar with the published book.

Before her reign as the Queen of Crime — which began, coincidentally, with the publication of The Mysterious Affair at Styles in 1920, exactly one hundred years ago — mysteries had conformed to certain traditions. Presented with wrongdoing, an eccentric detective (most notably, Sherlock Holmes) dogmatically deduced the solution from a series of obscure and cryptic clues. Christie certainly followed this pattern but very soon began to break rules, ultimately changing the whole game.

She is famous for having a murderer narrate one of her early books, something that had never been done before. More controversy greeted her homicidal child. Another killer arranges crimes from beyond the grave. A series of murders is used to disguise the one that matters to the killer. A despised victim is stabbed to death by a dozen different revenge-seekers. Two bodies are switched to confuse the timing. Multiple witnesses recount their version of the same death. And so on, challenging her readers again and again with then-innovative, intricate, and cleverly yet fairly clued story lines.

* * *

Still an apprentice in the murder field, I was not so bold as to attempt breaking new ground with my plot. Yes, I wanted to write an exciting and plausible mystery. But even more, I was looking for a girl named Aggie. If Agatha Christie could repeatedly alter the landscape of mystery writing, surely I could conjure a version of the child she’d been? What sort of girl grows up to plan and cunningly execute well over two hundred murders?

By her own record, Christie’s childhood was idyllic, living with her family in a cherished house named Ashfield, high in the hills of Torquay, with a view of the ocean. There is no evidence in Christie’s recollections of extraordinary devotion to the macabre, other than reading Sherlock Holmes and a habit of burying her pets with some pomp. She was an affectionate daughter, a pianist, a keen swimmer, and later a surfer; rumored to be one of the first women in Britain to stand up on a surfboard.

Christie’s father died when she was eleven. She wrote in her autobiography that this marked the end of her childhood. And this is where my book of fiction begins. Aggie has lost her familiar world. Papa is dead. Her grief provides the undercurrent of her responses to nearly every experience, from devouring a consoling cream puff at the neighbor’s genteel wake, to visiting the taxidermied lynx at the natural history museum, to discovering a dead body under the piano. (My own father was in decline while I wrote the book and had died by the time it went to the copyeditor. I was aware every day of the irony of writing about murder as a distraction from the loss of my very old dad, and I gave Aggie this same welcome diversion from her sadness.)

The First World War changed Christie’s life, as it did for everyone she knew and beyond. She volunteered with the British Red Cross, first at Torquay’s improvised hospital, where she fainted during her first assignment in the operating theatre. “After that…I used sometimes to turn my eyes away from the original incision with the knife,” she later wrote. She once had to help a new trainee “take an amputated leg down to throw into the furnace…then we cleared up all the mess and the blood together.” So much useful material!

She soon moved on to the dispensary and to studying for her examinations to become an apothecary’s assistant. Her thirty-four hundred hours of war work, between October 1914 and September 1918, gave her a profound knowledge of drugs, chemicals, poisons, and antidotes, the foundation for a career she did not yet know she would pursue.

Several years earlier, Christie and her sister, Madge, had been reading a favorite story together, The Mystery of the Yellow Room by Gaston Leroux, when Christie suggested that she’d like to try writing something similar.

“Well, I bet you couldn’t,” said Madge. “They’re very difficult to do.”

“I didn’t start to write it then,” said Christie, in her autobiography, “or plan it out; [but] the seed had been sown. At the back of my mind, where the stories of the books I am going to write take their place…the idea had been planted; someday I would write a detective story.”

Now, with Christie working as a dispenser, the time had come. And, “since I was surrounded by poisons, perhaps it was natural that death by poisoning should be the method I selected.” Medicine was Christie’s favorite profession for killers, and poison by far her favorite murder weapon, killing more than eighty victims by various ingenious methods, including cyanide in champagne, atropine-laced water, marmalade tainted with taxine, eye drops switched for insulin, nicotine in a gift of chocolates, digitalis in cocoa, morphine in tea, belladonna in cosmetics, extract of hemlock in beer, and arsenic in the sprinkles on dessert.

“Give me a decent bottle of poison,” she is credited with saying, “and I’ll construct the perfect crime.” (And perhaps it is fitting that my victim dies from a dose of rat poison stirred into a sugar bowl.)

For my first mystery, I culled certain facts from Christie’s youth and then made the rest up, paying homage to as many tropes as could fit and remembering always that my Aggie, without quite knowing it yet, is a writer in the making, gathering moments and people and colorful details for future use. She is hesitant and ignorant about immigrants — until she meets one. She has been oblivious to social custom that puts women’s minds and dreams in a second-class carriage — until her own are belittled. She has not considered just what it means to have someone leave one’s life forever — until her papa dies.

She is sharp-eyed and judgmental and a bit of a snoop. She may have inherited these traits from her paternal grandmother, Mrs. Jane Morton, who alternately rebukes and appreciates Aggie. Grannie Jane is a nod to Christie’s grandmother, whose wisdom and robust ethical standards contributed to the persona of Miss Jane Marple. My version is not as dithery as she is portrayed in Christie’s novels, but she does love gossip and contributes her share of wisdom and pith to any conversation.

Christie was always vague about the genesis of her other famous detective, Hercule Poirot, saying only that she remembered a community of Belgians hosted in Torquay during the First World War, fleeing the German invasion. Since Christie’s death, a name and a face have been uncovered by a journalist whose grandmother kept a record of the nearly five hundred refugees she had assisted during the war. At a fundraising event, the twenty-four-year-old Christie played the piano for a group of Belgians, one of whom was a retired policeman with a grand mustache, named Jacques Hamoir. Is it too far-fetched to imagine that the soloist and the displaced gendarme were introduced that night, planting the seed for a character who would become one of the best-known in the English language?

My Hector Perot is twelve years old, just like Aggie, boarding at the vicarage in Torquay until his family’s intended arrival from Belgium in a few months’ time. He, too, loves to read Sherlock Holmes, and he hopes to grow a grand mustache one day. He accredits the friction of his brain cells for his logical prowess and dismisses Aggie’s flights of fancy as “not helpful.”

Aggie, though, revels in imagining grim scenarios during the humdrum of daily life, like this moment of observing the vicar and his wife:

Mr. Teasdale nodded so vigorously that I expected to see his head topple off. Now that would be a colorful detail in a story, would it not?

Wrenched from its perch, the dislodged cranium rolled to a stop next to Mrs. Teasdale’s tightly laced boots. A geyser of blood erupted from the reverend’s stiff white collar and splurted heavenward.

My Aggie has just begun her calling as a detective. She has all the essential qualities: her Morbid Preoccupation, an affection for eavesdropping, and a suitably canny sidekick. The first paragraph of the book tells us she is taking her first steps toward being a writer as well:

I will tell first about making a new friend, and save the dead body for later. This follows the traditional rules of storytelling — lull the reader with pleasant scenery and lively dialogue, introduce a few appealing characters, and then aha! discover a corpse!

From the May/June 2020 Horn Book Magazine Special Issue: Breaking the Rules.


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