Stephen Sefton, a Spanish Civil War veteran still haunted by his experiences in battle, answers an advertisement in The Times and finds himself hired as secretary to Swanton Morley, an eccentric polymath and prolific author who has undertaken to write a series of guides to the 39 historic counties of England at the prodigious rate of one a month.
On their first assignment, published as The Norfolk Mystery, they got caught up in a murder. Death in Devon, the second in the series, takes place a week after the events of the previous book, as Morley is invited to give a speech at a school run by an old friend. Naturally, there is another murder. Or was the death of a schoolboy whose body is found on the beach, having apparently driven off the cliff in the dark, an accident?
Of course it wasn't. Don't be silly.
The 'Golden Age' of cosy English crime fiction is fashionably maligned these days. There's no point trying to persuade anyone of its merits at this stage. You either get the appeal or you don't.
Ian Sansom, an English writer based in Northern Ireland, has embarked on a series for those of us who do "get" it, and it really couldn't have been done better.
There's not much of a mystery here. A boy dies. A cow is found mutilated. Some chickens go missing. There are shenanigans involving secret caves and occult practices.
The plot, though, is largely irrelevant. It's all in the telling. Too clever by half, self-absorbed, infuriating, but loveable too, Professor Morley has an archetypal quality which makes it seem as if he was found by Sansom rather than invented.
His daughter Miriam, a spirited young woman with a penchant for unwise love affairs, and who "often spoke like someone trying to get around the Hays Code", is another pitch-perfect creation.
Then there's Sefton himself, the still centre of this curious world, whose role is often simply to ask the right questions, but who is an absorbing character in his own right, with a great line in mordant humour.
When told that one character is influenced by the surrealists, he remarks drily: "He certainly looks like a man who might be influenced by the surrealists."
The book is suffused with a rich vein of comedy, which runs the gamut from understated (badgered at a book signing by a woman who knew Edward Bulwer-Lytton in his later years in Devon and considered the Victorian man of letters to be a genius, Morley observes that "perhaps it is easier to appear exceptional in Torquay than it is elsewhere") to downright saucy (one of the Professor's publications is a piano primer for children called 'A Boy's First Fingering').
Most of all, there's Sansom's manifest love of words and obscure arcana and minutiae; his pleasure in having found a form which can contain them is infectious.
There are darker touches - finding himself lost in a cave, Sefton is assailed with memories of war - but it's the nostalgic atmosphere and playfulness which dominate. Death in Devon is riddled with lines that demand immediately to be shared: "If there is anything worse than being lied to, it is being lied to by two people, neither of whom is aware that the other person has been telling a different lie."
It's hard to think of a recent work which provides such pure, unadulterated delight. Next stop, Westmorland. Here's hoping Sansom is hard at work, heeding his hero's advice:
"No shirking. No shilly-shallying. No funking." There are 37 counties to go. We're waiting.
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