Published in 1935, Three Act Tragedy was the eighth novel by Agatha Christie to feature Hercule Poirot. It is unusual among (early) Poirot novels in that Poirot is not the main detective in the story.
The basic setup is that Famed Actor Sir Charles Cartwright is hosting a dinner party at which Poirot is attending (I can’t recall why Poirot was in the neighborhood; he might have been retired at this point) and one of the attendees of the party—a charming older vicar—keels over dead with no obvious cause. A few months later, one of the other attendees at the party, a psychiatrist by the name of Sir Bartholomew Strange, keels over dead at a party at his own house in the same way. This time instead of attributing it to heart trouble, it is discovered that he died of nicotine poisoning. Sir Charles and another of the guests, Mr. Satterthwaite, investigate, along with a precocious young woman who goes by the nickname Egg. The three occasionally consult with Poirot during their investigation, which is his involvement until he reveals the murderer at the end.
NOTE: there are spoilers after this point.
This book was very much about the theater, or at least about theatrics. It begins and ends with theatrics, and much of it is taken up with the theatrical personality of Sir Charles Cartwright. It is even divided into three acts which are titled, in theatrical terms, Suspicion, Certainty, and Discovery. It’s a bit hard to relate to this; stage actors are a different breed from movie actors. By 1935 movies were well on their way to replacing the theater as the dominant form of acting-based entertainment, but this novel was not really about 1935. Sir Charles had retired from the stage by now; Three Act Tragedy was about the aftermath of things that had been, not things that are currently.
The most memorable scene, to me, was Sir Charles employing his acting skill to reconstruct what the butler Ellis had done based on clues and to find the sheets of paper which no other detective had found. It’s a vivid scene, but it is diminished in the recollection by the fact that Sir Charles had planted the papers there himself, and Ellis had not, in fact, been interrupted.
The story is well constructed and like most Christies, the plot is original and clever. The murder of the vicar being a dress rehearsal for the murder of Dr. Strange was certainly an original motive for murder and yet a plausible one. Not so plausible when described as Sir Charles following his actor’s instincts and doing a dress rehearsal, but if it’s not presented so theatrically, testing out a type of poisoning which is supposed to go undetected on a victim to whom one has no motive to kill him is reasonable, if diabolical. But demons still have their reason, and it makes sense.
It’s also curious that this book ends with an explanation that was probably much inquired about Poirot:
“You’ll excuse me—” said Mr. Satterthwaite.
“Yes, there is some point you wanted explained to you?”
“There is one thing I want to know.”
“Why do you sometimes speak perfectly good English and at other times not?”
“Ah, I will explain. It is true that I can speak the exact, the idiomatic English. But, my friend, to speak the broken English is an enormous asset. It leads people to despise you. They say—a foreigner—he can’t even speak English properly. It is not my policy to terrify people—instead I invite their gentle ridicule. Also I boast! An Englishman he says often, ‘A fellow who thinks as much of himself as that cannot be worth much.’ That is the English point of view. It is not at all true. And so, you see, I put people off their guard. Besides,” he added. “it has become a habit.”
That is not the actual ending, though. A little after this comes the true ending:
Mr. Satterthwaite looked cheerful.
Suddenly an idea struck him. His jaw fell.
“My goodness,” he cried, “I’ve only just realized it. That rascal, with his poisoning cocktail! Anyone might have drunk it. It might have been me.”
“There is an even more terrible possibility that you have not considered,” said Poirot.
“It might have been ME,” said Hercule Poirot.