Agatha Christie is the best-selling novelist of all time.
But in 1916, she wasn’t even the most promising writer in her family.
Her older sister Madge had already written several short stories,
while Agatha hadn’t published any.
So when Agatha shared her desire to write a mystery novel,
Madge scoffed.
She bet that Agatha wouldn’t be able to create a compelling mystery—
and certainly not something she couldn't solve.
Today, the novel that came of that bet
stands alongside almost 100 other mysteries written by Christie,
each one a cleverly constructed puzzle box
of clues, misdirection, and human drama.
So let's investigate how she crafted these perfect crimes.
Christie designed her stories in many ways,
but one of the most important decisions was the setting.
From a remote island to a snow-stalled train car,
she favored locations isolated from society.
By restricting the scope of her stories,
Christie limited possible suspects and built tension
by forcing characters to stay put—
even with a killer among them.
Sometimes she further heightened the drama
by making the characters strangers,
unsure who they can trust.
But while her settings are eerie and extraordinary,
her characters are just the opposite.
One of the biggest criticisms of Christie’s novels
is that they’re full of two-dimensional people.
But Christie avoided complex characters for a reason.
By reducing people to a handful of simple traits,
she provided readers with predictable suspects.
Well, usually predictable.
Christie also used the audience's expectations against them.
However, this typecasting sometimes relied on
what contemporary readers know to be harmful stereotypes.
She frequently caricatured particular occupations and ethnic groups
for comic effect,
reinforcing the prejudices of her time.
This is certainly not an element of Christie’s work worth emulating,
and fortunately, many modern mystery writers
have found less problematic ways to use this technique.
Even when she got it wrong,
Christie worked to make her characters feel authentic.
She closely observed the people around her,
and constantly scribbled down details from overheard conversations.
She would then rearrange these details to piece her mysteries together,
often switching who the murderer was as she worked.
This approach kept information murky and disoriented even the sharpest readers.
However, there’s an important balance to strike
between being clever and being confusing.
Nobody wants to read a predictable mystery,
but if things get too convoluted you can lose your reader altogether.
Christie handled this in part by keeping her language simple and accessible.
She used short sentences and clear, snappy dialogue
to help readers follow information.
This kind of clarity is essential,
because the best mysteries string their audience along
with a carefully laid trail of clues.
With Christie, a good clue is one the reader will remember,
but usually, fail to completely understand.
For example, when a character cries that “Everything tastes foul today,”
just minutes before he dies,
the reader races to determine who poisoned his beverage.
But they’re likely failing to truly consider this clue.
If everything tasted foul that day,
then he’d been poisoned long before that drink.
Christie also used clues to intentionally mislead her audience.
For example, readers might recognize a clue associated with one suspect,
only to learn that it was being used to frame them.
Other times, she built misdirection directly into the story’s structure—
like when a narrator reporting the murder is revealed to be the killer.
Outside crime and clues,
there’s one more ingredient in Christie’s formula:
the detective.
Christie created many sleuths,
but her most enduring are Hercule Poirot and Miss Jane Marple.
Neither this petit Belgian refugee nor this elderly amateur detective
are traditional heroes.
But their outsider status is exactly what helps them slip past security
and make suspects let their guard down.
As you might have guessed, Agatha won her sister’s bet.
Her eccentric detectives, clever clues, and simplified suspects
form a blueprint that has stumped countless readers.
And now that you've uncovered her strategies,
the only mystery left is what stories you can tell with these secrets.