Anthony Berkeley’s Poisoned Chocolates Case has gotten a lot of praise over the years, and deservingly so – but no reviewer to my knowledge has ever noticed what in my opinion makes it a truly unique experiment.
Mysteries aim at finitude – the story is over once the puzzle is solved; there is nothing or little to add unless you decide to write a sequel, that is, another book. Poisoned Chocolates is different as its very concept means that it can be expanded again and again with no end in sight; all it takes is coming up with a further solution to the titular problem. Only two authors so far have risen to the challenge: Christianna Brand in the Eighties then Martin Edwards when the book was reprinted four years ago as part of the British Library Crime Classics series, but there is no reason to stop there. Anyone clever, imaginative and of course talented enough can contribute to what remains to this day a work-in-progress.
Knowing Berkeley as we do, there is no doubt he had that peculiarity in mind from the start. Poisoned Chocolates Case is not merely a gratuitous display of plotting virtuosity; it is the first of several attacks from the author on the very foundations of the detective story.
What Berkeley tries to prove there is that the « logic » behind the genre is merely author’s fiat, as there is nothing irrefutable about the detective’s reasoning; it is only one possible interpretation of the facts among many others. (How convenient that « culprits » always end confessing or commiting suicide!) Thomas Narcejac then Pierre Bayard would later make the same point.
That it is still possible to add new chapters to the book almost one century after it was published proves how cunning and perceptive Berkeley was and how on-target his point was. It also leads one to wonder whether other detective stories really are as finite as they seem to be. « Subversive » is a word often used indiscriminately nowadays but it certainly applies there.