Courtesy of ITV Global Entertainment Ltd

Although it never quite lives up to the ingenuity of its initial inspiration (murder by witchcraft), this is still one of Agatha Christie's clever, tricky stories of obsession and murder, inviting adaptation either as an interesting psychological study or as an exercise in sustained suspense. Maddeningly, producer Adrian Bate and writer Alma Cullen rejected both approaches. The story is sufficiently complex, and they made it more so by emphasising virtually every kind of irrelevant detail; the characters are interesting, but they have been smothered in unrevealing trickery.

Set in the culturally transient period of the 1960s (Christie's novel was first published in 1961), the film, rather awkwardly, hovers somewhere between the monochrome mysteries of the 1961-1964 Margaret Rutherford/Miss Marple films and the modish excesses of Antonioni's 1966 Blowup (garishly coloured mini-skirts, trendy art galleries, a forced air of high-spirited youthfulness).

The busily involved plot - including conspiracy, an unusual array of red herrings, and pursuit by the law in the form of a relentless police inspector - has some vividly bizarre moments, notably by a trio of Macbethian witches living in an old cottage, once an inn called The Pale Horse.

These three, central to the plot but peripheral to the action, extract the maximum amount of ghoulish behaviour from their rather sketchily written parts. Magisterially grotesque in their black ensembles, the self-proclaimed witches - Thyzra (Jean Marsh), Cybil (Ruth Madoc) and Bella (Maggie Shevlin) - are prone to engage in enthusiastic ritual sacrifice of cockerels on their kitchen table.

Much of the effect of this whodunit depends on its 'trick' solution. The story, in fact, relies on a series of tricks and coincidences, beginning with its enjoyably implausible central situation (hysterical implications of black magic curses), and the story works only to the extent that the viewer retains a certain curiosity about its outcome.

Since the script is as much concerned to cover up motivation as to reveal it, the playing tends to be somewhat overstated: Colin Buchanan's tense, aggressive hero, investigating endlessly; Jayne Ashbourne's plucky girlfriend; Michael Byrne's suspiciously inhospitable, wheelchair-bound local squire; Trevor Byfield's incredibly stubborn policeman; and Leslie Phillips's smoothly sinister murder broker.

A curious Christie TV film, but an interesting one, and certainly one of the better 'modern' TV translations of her work.

Tise Vahimagi

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