Whodunnit fiction is all about the puzzle – finding the who, what, where, when and why of a mystery which usually involves a corpse and a handy group of suspects corralled in a country mansion, or similar, ready to be interrogated by a singular detective. But there is a subgenre of whodunnit fiction that is mostly about the how. I’m speaking, of course, of locked-room mysteries.
Whodunnits allow the reader to believe that they can beat the detective to the solution. But locked-room mysteries are not so generous. They taunt the reader with an impossible puzzle – how was the victim murdered inside a room which is locked from the inside? There are no windows. No roomy chimneys through which a murderer could escape. And no secret passages.
I always believe that I might be able to solve a whodunnit, though I rarely do, but I know that the solution to a locked-room mystery is almost certainly beyond me, even after reading John Dickson Carr’s famous Locked Room Lecture. The ‘lecture’, which can be found in Chapter 17 of his novel, The Hollow Man, published in 1935, sets out the seven possible solutions, which can be summarised as: The victim killed himself by accident, by design, or at the inducement of some malevolent third party; the victim was killed by some kind of ‘device’ which is disguised as an innocent piece of furniture or other article still inside the room; the victim was killed before the door was locked, or after the door was opened, despite evidence to the contrary, which has, of course, been fabricated by the murderer; or the murderer managed to somehow commit the murder from outside the room even though this seems impossible.
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Dickson Carr was a master of the locked-room mystery. In addition to The Hollow Man (alternatively titled The Three Coffins), he wrote The Crooked Hinge and The Judas Window (the last under the pen name Carter Dickson), all considered classics of the genre, and all just as mystifying.
The Murders In The Rue Morgue by Edgar Allan Poe may have given birth to the genre, with the death of two women in a fourth floor room, locked from the inside. Poe’s solution (no spoilers here!), however, would not be considered an impossible puzzle today because the solution needs to be logically deducible and, crucially, human.
The first true locked-room mystery is thought to be Israel Zangwill’s The Big Bow Mystery, first published in 1892. The solution does, indeed, conform to one of the methods Carr outlines in his lecture.
Although the genre is an old one, and although the possible solutions are limited to only seven, there are endless permutations of the locked-room puzzle, which is still outfoxing readers all over the world.
Paul Halter is a French crime writer who has made impossible mysteries a speciality. Unfortunately, to date, only a few of his novels have been translated into English, but The Seventh Hypothesis is a particular favourite of mine. A celebrated mystery writer and an equally celebrated actor enter into a bizarre pact: each of them will commit a murder and try to pin that murder on the other. The victim disappears from a corridor from which there is no exit, and which is kept under observation. The body reappears in front of a policeman in a place where the policeman has just searched. Which of the men is responsible for the murder, and how does the detective know which evidence is real and which has been planted by the writer or the actor in order to incriminate the other? Genius!
Equally devilish is The Tokyo Zodiac Murders by Japanese author, Soji Shimada, which combines the traditional locked-room mystery with a Frankenstein-esque murderer who appears to be building a monster from body parts taken from his victims.
My favourite modern locked-room mystery, though, is Stuart Turton’s fantastic novel The Seven Deaths of Evelyn Hardcastle which gives an entirely new twist to the genre by placing the detective in their own kind of locked room, from which they can only escape by solving the murder before their memory is wiped clean.
I was able to solve none of these locked-room mysteries and could only sit back and enjoy it. When I came to write my own whodunnit The Game is Murder, however, I was excited to create my own impossible puzzle, and challenge the reader to solve it. I hope that they have as much fun reading it as I have had writing it, whether they discover the solution or not!
