Agatha Christie's Marple: Endless Night, ITV

“Her most devastating surprise ever.” Thus spake The Guardian, a quote happily slapped across the cover of the first paperback edition of Agatha Christie’s 1967 thriller Endless Night. While I wouldn’t go quite that far – that honour goes to her still startling, genre-busting The Murder of Roger Ackroyd (1926) – it’s a compelling little chiller. Small wonder that ITV wanted it for their franchise.

In her most Ruth Rendell or Barbara Vine-like book, Christie created not a whodunnit but a suspenser, the story of chancer and chauffeur Michael who meets and marries heiress Ellie and builds his dream house. The site overlooks miles of uninterrupted countryside but carries a mysterious local curse. 

Like the BBC’s Eighties Miss Marple with Joan Hickson, the best of these adaptations work because the productions don’t condescend to the material. And unlike the later Poirot episodes where art direction appeared to be valued over action, director David Moore never lets period clothes, cars and locations stall the momentum of his slow-burn drama. With its doom-laden, William Blake-derived title, plus its class conflicts, gypsy warnings, twisty deceits and of course deaths, there was more enough in the book to inspire a film version in 1972 featuring a torrid score complete with fashionable Moog synthesiser by Hitchcock’s favourite composer Bernard Herrmann. It was a dud not least because of leaden filmmaking and performances from Hywel Bennett, Hayley Mills and Britt Ekland. Mercifully, their work is trounced by this altogether stronger and subtler cast led by Tom Hughes, Joanna Vanderham and Birgitte Hjort Sørenson of Borgen fame (pictured above).

The rhythm is dictated by the continual use of Michael’s voiceover. It’s a device routinely regarded as the refuge of the dramatically inept, but with the entire original novel written in Michael’s first-person narration it is, for once, entirely apposite. That’s particularly true because – major spoiler alert – his version of events is slowly revealed to be less than reliable, a cunning piece of misdirection.

Elyot significantly increases tension by bringing Miss Marple in for the kill

Aside from the necessary contrivance of McKenzie’s beady-eyed, effectively downplayed Miss Marple popping up in different countries and thus running into Michael before and during his honeymoon, Elyot’s reworking strengthens the structure. His arresting pre-credit sequence, deftly repositioned from very late in the novel, tightens the drama. It sets up the high-stakes tone and turns the novel’s wildly implausible architect character into someone interestingly linked to Michael.

The casting pays dividends, even in small roles like Michael’s plain, worn-out mother played by a game Tamzin Outhwaite who is both unrecognisably plain and quietly strong. Better still, Birgitte Hjort Sørenson is clearly having a ball as Ellie’s best friend Greta, a smouldering German temptress who gets in the way. Far from being attention-grabbing star-casting, she’s the real deal (see also, if you can, her performance as wife to Tom Hiddleston’s Coriolanus at the Donmar Warehouse).

Barely off-screen throughout, gaunt Tom Hughes is the pivot of the entire story. Measured and softly spoken, he makes the ideal choice of being a wholly convincing liar, neither character nor actor overplaying his hand and thereby retaining the viewers’ fascination even after the twist is revealed when sympathy should be sacrificed.

The weakest element of the novel is the ending that unravels in the same way as the over-explanatory postlude to Psycho. While remaining true to Christie’s psychology, Elyot significantly increases tension by bringing Miss Marple in for the kill. This leads to a vivid sequence of climatic confrontations and character-driven pay-offs that improve upon the original. What more could you ask of an adaptation?