Agatha Christie knew 14 ways to kill a man

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This week's question: How accurate were Agatha Christie's descriptions of poison?

Short answer: Deadly accurate. Christie knew her stuff.

In honor of the Queen of Crime's 125th birthday, we're delving into all the deadly details of her crime novels. The mystery master remains one of the bestselling authors of all time. (The only bestsellers ahead of her are Shakespeare and the Bible, both of which had a pretty big head start.)

In her 66 novels, Christie led dozens of characters to their deaths. She wrote about stabbings, drownings and even a strangling with a ukulele string — but poisons were her first love. More than half of her murder victims kicked the bucket due to poison.

"They can't be poisoned every time," she reportedly said. "But I am happier when they are."

Her fascination with poisons started during World War I, when a young Christie worked as a nurse and apothecary's assistant. She later earned her chemist's license (a precursor to a pharmacy degree) after studying under quite the memorable teacher: Her mentor carried a vial of poison in his pocket wherever he went, because it made him "feel powerful."

Surrounded by potentially lethal chemicals, Christie's imagination went to work. In "A is for Arsenic," Kathryn Harkup, a chemist herself, offers a detailed account of Christie's fascination with fatal ingredients. She runs down the list of Christie's favorite poisons: arsenic, cyanide, digitalis, hemlock, nicotine, opium, phosphorus, ricin, strychnine...

Some have actually accused Christie of being too accurate. In 1977 in France, an office worker killed his aunt with poison eye drops. When officials searched his apartment, they found one of Christie's Miss Marple books on the shelf, with the passages on poison underlined.

That same accuracy has come in handy, however, for medical professionals. There are anecdotes aplenty about nurses or doctors recognizing key signs of poisoning based on Christie's novels. Where else would you study up on the symptoms of thallium poisoning in your everyday life?

Christie's deep knowledge of poisons — and her characters' ability to get their hands on them — is a byproduct of her historical moment. In the first half of the 20th century, Harkup notes, substances that are now heavily controlled were easily available for the average citizen.

Opium was available over the counter. Cyanide was in the gardener's shed. You could get foxglove or hemlock from a plant trimming, and morphine and strychnine weren't hard to obtain.

Arsenic was the easiest of them all — poisonings with arsenic were so common, the French nicknamed the substance "inheritance powder."

In Christie's books, the murderers often hid the fatal doses in medications, like heart pills or nasal spray. She also delighted in writing about poisoned foods, be they whipping cream or marmalade.

One daring French author, Anne Martinetti, has actually compiled two cookbooks full of Christie's recipes — poison optional, we assume.

Try a few recipes out at your next dinner party — Delicious Death Cake, anyone? — but don't be surprised if your guests politely decline.