Agatha Christie's investing mysteries: Case closed

"The little grey cells, Mon Ami!"
In other words: use your brains, my friend!
Yes, you've guessed it! I am talking about Hercule Poirot—Agatha Christie's immaculate Belgian detective, who solves murders with nothing but a waxed moustache, a love for order, and the sheer power of his brilliant mind.

But what if I told you that Poirot can also teach you a thing or two about money? About investing smartly? About avoiding the financial equivalent of a murder mystery?

Let's step into Poirot's world and see how his investigative skills apply to the equally puzzling world of money, markets, and investments.

1. The importance of details: Small clues, big revelations

Poirot often says, "It is the brain, the little grey cells on which one must rely. One must seek the truth within—not without." The same holds true for investing.

In the detective's world, a tiny clue—a slip of the tongue, a mismatched detail—can solve the case. In the investing world, the equivalent might be a small inconsistency in a company's financial statement or an unusual entry in the balance sheet.

Take the downfall of companies like Enron or Manpasand Beverages. What went wrong? Investors ignored or didn't spot red flags hidden in the numbers. Had they been more attentive to the details—like strange changes in cash flow or suspicious accounting—they might have escaped the fallout.

Moral of the story? The truth is always in the details. And the details don't lie.

2. Understand people, not just numbers

Poirot doesn't just chase fingerprints—he studies people. "It is the psychology I seek!" he often says.

And that's the trick to investing too. Because markets are made up of people. Emotional people.

Sometimes, everyone starts buying the same stock—not because the company is doing well, but because everyone thinks it's going to do well. That's how bubbles form. The dot-com crash of the late '90s and the 2008 financial crisis were perfect examples. Hype took over logic.

If you can read the mood of the market—just as Poirot reads his suspects—you can stay one step ahead. Recognise when people are being greedy or fearful, and don't get swept up in it.

3. If it sounds too good to be true... it probably is

Christie's stories often feature fraudsters who promise easy money. From fake bonds to dubious investment schemes, the warning signs are always there—for those who pay attention.

Real life had its own Christiesque crime: Bernie Madoff's Ponzi scheme promised high returns with no risk. Many trusted him blindly and lost everything.

Poirot would never fall for that. Neither should you. High returns with low risk? It doesn't work that way. Always be wary of offers that sound too perfect. Ask questions. Dig deeper.

4. The psychology of greed and risk

Ever heard of a tontine? In Christie's universe, it's a creepy but clever concept: a group pools money, and as each person dies, the survivors inherit more. The last one standing gets it all.

It's morbid. But it teaches something important about how people behave when money and time are involved. Greed, impatience, risk—these are forces that move both markets and murderers.

Understanding your own reactions to risk—and other people's—is key to good investing.

5. Times change. You must change too

Poirot may love order and routine, but he lives in a changing world. Early Christie novels are full of old money—land, inheritance, titles. But as the series progresses, we see the rise of stocks, cash, and the business of modern finance.

Same goes for real-world investing. Once upon a time, Kodak was a household name. But it didn't adapt to the digital age and collapsed. Meanwhile, Instagram, built for the digital world, was worth a billion dollars within two years.

Lesson? Don't cling to the old just because it's familiar. In finance, those who adapt survive.

6. Never put all your eggs in one basket

Poirot believes in keeping an open mind—and so should you.

In Hickory Dickory Dock, students lose money by trusting one person too much. Investors do the same when they pour all their savings into one stock or one type of asset. If that stock crashes, everything is lost.

Remember Lehman Brothers? One bad bet on risky assets and it brought down an empire.

So spread your investments—across different companies, industries, and types of assets. That way, even if one fails, others can keep you steady.

7. Stay calm when things go wrong

When a murder occurs, Poirot doesn't panic. He observes. He thinks. He waits for the fog to clear.

Investors must do the same. In 2008, the stock market crashed. Many panicked and sold everything. But those who stayed calm, thought clearly, and held on saw the markets recover—and grow stronger.

Patience is power. Especially when everyone else is running scared.

8. Question everything. Always.

Poirot never accepts anything at face value. "Everything must be examined. Everything must be accounted for."

That's exactly how you should approach investing. Don't believe everything you hear on social media or from self-proclaimed "finfluencers." Don't trust a company just because everyone else is buying it.

Study the numbers. Read the reports. Look for what's not being said.

The Enron scandal and the 2008 housing crash were both disasters that could've been spotted—if only more people had asked the right questions.

The Poirot Portfolio: A mindset for all markets

Hercule Poirot doesn't solve crimes with luck. He uses reason, scepticism, psychology, and patience. And those, my friend, are the exact traits you need to succeed in investing.

So, next time you're checking your portfolio or reading about the next "hot tip," take a breath.

Use your little grey cells.

And invest like Poirot.

Also read: Fluent in finance? Me neither.

This article was originally published on April 15, 2025.