Agatha Christie’s 1936 novel The ABC Murders (also known as The Alphabet Murders) is her first stab at a serial killer story. Sorry – couldn’t resist the pun.

She followed on from Philip MacDonald’s opening foray into the sub-genre X v Rex, published in 1934 under the alias of Martin Porlock. This book, written from the perspective of the killer – the so called inverted style in which the suspense is generated by whether or not the killer, whom the reader already knows, will be caught rather than trying to solve whodunnit – begins to explore the psychology of the murderer. In this it has similarities to the earlier Malice Aforethought by Anthony Berkeley, writing under his Francis Iles pseudonym, in 1931.

Christie also purported to examine the psychology of the criminals – indeed, you could argue that much of Miss Marple’s detecting follows a psychological profiling approach – finding similarities in patterns of thought or behaviour that follow archetypes she has observed in her village of St Mary Mead. However, Christie never felt the explication of the criminal psyche should ever be anything but subordinate to the plot.

But then Christie only used her own name for her detective fiction (she reserved her alter-ego Mary Westmacott for romances), so she was to an extent hidebound by the public’s expectations of “the next Christie”. Both MacDonald and Berkeley made use of pseudonymous novels to explore new avenues to writing detective fiction in a way that Christie chose not to. They were thereby freed from the constraints of audience expectations by taking this approach.

In fact, Christie’s approach in The ABC Murders is innovative, mixing conventional first person narrative through her usual character of Captain Hastings, with narrative from the perspective of the killer.  She finesses the latter sections through the device of a purported reconstruction of the killer’s perspective after the fact by Hastings (with the benefit then knowing of Poirot’s solution) for his telling the story in the book. This is mixed with the introduction of actual letters from the killer addressed to Poirot, which give the killer a voice on the page. Such a mix of narrative perspectives had been done before – as early as 1868, Wilkie Collins was experimenting with this approach in his detective novel, The Moonstone.

What makes Agatha Christie’s entry into this multiple-perpective, serial killer world more significant than the more ambitious works of Anthony Berkeley/Francis Iles and Philip MacDonald/Martin Porlock is the size of her market. She was selling vastly more books than the others. Therefore he influence was commensurately greater.

I would argue, therefore, that The ABC Murders is one of the most significant Golden Age novels and a vital step out of the cozy and into the murkier, much more sinister world of the serial killer. Without her breaking the ground with the mass audience, the seeds could not have been sown which later bore fruit in the multitude of later novels which we see now featuring serial killers driven by innumerable warped psychotic impulses.

So it’s Agatha I have to thank for the sleepless nights I now endure having been “creeped out” by the visceral, nightmare visions I have subjected myself to, reading the likes of everything from Mark Billingham’s Tom Thorne books to the gruesome finds of Patricia Cornwell’s Kay Scarpetta.

Mark