The ABC Murders, episode 3, review: A perfectly conventional conclusion after two hours of grim revisionism

After two hours of grim revisionism the big twist in the final episode of the new BBC1 adaptation of Agatha Christie’s The ABC Murders is its perfectly conventional conclusion. Christie devotees fed up being biffed over the head with Brexit analogies and Christopher Nolan-esque stylised gloom will be relieved as the lavish mini-series belatedly reverts to Professor-Plum-in-the-Study-type shenanigans.

It also continues to benefit from a mercurial central performance from John Malkovich, who, donning the overcoat of Hercule Poirot, adds 50 shades of PTSD to the inimitable detective.

The bloody puppeteer behind the eponymous killings is unmasked as none other than Poirot’s old pal Franklin Clarke (Andrew Buchan). The clubbable killer has embarked on his murderous campaign as distraction from his violent toppling of older brother Sir Carmichael Clarke, whose titles and whopping huge mansion he hopes to inherit.

But even before working his way up to Carmichael – the “c” in his alphabetic countdown of victims – he discovers he’s developed rather a taste for stabbing, coshing and strangling with tights. All of this Poirot pieces together after Franklin repeats a line already fed to the detective by the presumed guilty party – oddball travelling salesman Alexander Bonaparte Cust (Eamon Farren).

The troubled and malleable Cust is revealed be a naif taken advantage of by the true villain. Under the pretence of helping out a fellow fallen on hard times, Franklin has arranged so that the salesman will be at the locations of killings the very day the dastardly deeds are done.

And he is only getting started. Carmichael’s terminally ill wife Lady Hermione (Tara Fitzgerald) would probably have expired before Franklin got to her. However, the killer’s own lover and co-conspirator Thora Grey (Freya Mavor) would, Poirot guesses, ultimately be for the chop too.

But Franklin has reckoned without Poirot’s genius – and the detective’s lingering suspicion that the writer of the taunting “ABC” letters sent to Poirot are the work of a person mimicking the voice of another. He’s correct – it’s Franklin, pretending to be Cust in order to draw Poirot into the game. Upon being rumbled, Franklin will insist this is his attempt to cheer up Poirot, whose crime-fighting career has hit the buffers.

Less satisfactory once again are the secondary motives of writer Sarah Phelps and director Alex Gabassi. If Peter Ustinov’s beloved portrayal of the barnstorming Belgian was the equivalent of Sixties-vintage Batman – jolly and over the top – this new imagining sees Poirot entering his Dark Knight phase.

Malkovich gives us Poirot as brittle survivor – traumatised by his flight 20 years previously from war-torn Belgium and an eager bearer of grudges. The actor is glumly charismatic – but the ennui is trowelled on so that it becomes a distraction rather than, as presumably intended, encouraging empathy with the rather stiff sleuth.

He even gets a superhero origin story as we learn of his secret past life as a priest who witnesses his congregation burnt alive in a church by invading Germans in 1914 (a contrivance original to Phelps). Just as egregious is the clunking drawing of parallels between the forces of extremism sweeping Thirties Europe and the tectonic idiocy that has led to Brexit.

“Such vapid nostalgia for the gentle past,” observes Poirot as he scans alarmist newspaper headlines in disgust. Elsewhere he angrily rips down a British Union of Fascists poster declaring “March for England. We Must Stem the Alien Tide”.

These attempts at injecting contemporary urgency into Agatha Christie are horribly heavy-handed and, anyway, this is a fight Phelps and Gabassi cannot win. Ultimately, it is Christie’s mastery of byzantine plotting that elevates The ABC Murders.

Thus the true lesson runs contrary to Poirot’s musings on the pointlessness of pining for the past. Some things indeed are worth waxing nostalgic for. The ABC Murders reminds us Agatha Christie’s delicious period whodunits are chief among them.