Close the curtains, settle the children, fret the hearth: the BBC Classic Serial, television’s annual tribute to mists and mellow fruitfulness, returns to BBC One tomorrow night. The latest adaptation of a Victorian masterpiece is everything you could want and, what is more, everything you would expect. Hark the opening dialogue. Two bonneted maids of a familiar visage enter a darkened room and begin to bustle. “Open the curtains, Matilda,” says Eileen Atkins to Judi Dench, “while I remove the dustsheets from the furniture.”

The speech is a perfect statement of the adapter Heidi Thomas’s intentions towards Cranford, a novel – actually three novels – by Elizabeth Gaskell that you will almost certainly not have read. This production, with its outstanding cast, sumptuous visual values and careful modulation between sentiment and humour, blows the dust off a forgotten classic. Whether or not we shall be convinced entirely by the adapter’s premise that all human life is to be observed in 1830s Cheshire, it is hard to disagree that this is what the BBC is here to do. ITV’s drama controller had a quick response when I asked if her network would have made it. It was: “No”.

There are problems with the current craze for classic adaptations, however. The first is that most of the books being reopened by television have not been gathering dust. Cranford is an exception, a five-year obsession for its producer Sue Birtwistle. But look at what else is around.

After a year in which Jane Austen took up residence in its spring schedules, ITV gave us E. M. Forster’s/ Andrew Davies’s A Room With a View two weeks ago. It was clever and affecting, but moved the Radio Times to ask on its cover: “Why another adaptation? And why now?” ITV’s Christmas treat will be an adaptation of The Old Curiosity Shop starring Derek Jacobi. Next year it makes Wuthering Heights, just nine years after its last version.

On the BBC, meanwhile, stand by for Sense and Sensibility, by (again) Andrew Davies – and don’t say you still haven’t watched the Kate Winslet version that your auntie gave you on video ten Christmases ago. You may be less familiar with Little Dorrit(unless you recall the 1988 Derek Jacobi film) and Lark Rise to Candleford(unless you saw the National Theatre’s ambulatory production in the 1970s), but you could probably write an essay on the plot of Oliver Twist, which the BBC is also remaking.

“We worked out it had been done 49 times,” laughs Kate Harwood, the head of series and serials at the BBC, arguing that the EastEnders writer Sarah Phelps has brought a “strong London voice” to the piece. Each generation of actors deserves its turn at the greats and she is enthusiastic at having secured the services of Timothy Spall as Fagin and Tom Hardy as a “sexy and dangerous” Bill Sykes. “But,” she adds, “Dickens is catnip for actors.”

Like many of the canon’s authors, he is irresistible too to commissioners, directors, DVD merchants and publishers (whose sales of out of copyright work soar). Finance directors crave the foreign sales they provide. In Australia, ABC fêtes a BBC period drama with as much fanfare as anything it produces itself. In America the BBC has long enjoyed partnership deals with WGBH in Boston – Cranford is another beneficiary – but as it launches new commercial channels abroad, it is the petticoat lines that drive subscriptions. For ITV it is more important that the advertisers are happy. And they are. Of the 3.8 million who watched A Room With a View almost half were ABC1s, exactly the affluent audience ITV finds hard to reach. Teachers will also rejoice – although executives deny that they check out the national curriculum’s set texts before they commission their adaptations.

But how much, except at the margins, can each new version add? Two years ago Bleak House broke the mould by becoming a “soap”, going out in twice-weekly half hours; Oliver Twist will follow its frequency. There are reinterpretations to make. Sandy Welch adapting the BBC’s Jane Eyre last year emphasised more than is usual the heroine’s time away fromThornfield Hall and had Jane eventually succumb to Rochester only after first giving the MCP a good ticking off. Davies’s A Room With a View revved up the class war latent in Forster’s novel and strongly hinted that Cecil Vyse was not the marrying type because he was, well, gay.

We may harbour hopes, too, for ITV’s Wuthering Heights since it has been written by Peter Bowker, who, with great originality, wrote the BBC’s musical thriller Blackpool. But Bowker must know his main job is to deliver viewers and prestige to ITV. As Laura Mackie, ITV’s new head ofdrama, says: “I would struggle to point to a definitive TV version of Wuthering Heights, in the way you can with Andrew Davies’s Pride and Prejudice. That’s a challenge for us, to try and do the definitive version.”

It was Davies’s Middlemarch in 1994 that turned the classical adaptation from a viewing chore to a treat. His tools were low humour, classy sex, a modern intelligence and a budget to die for. This is not denigration. It is hard now to recall how unacceptable classical adaptations had become. From Sunday afternoon Dickenses that masqueraded as children’sprogramming, to the grand Forsyte Saga, which included production values so low that when Soames’s coat fell off its hook it stayed on the floor, these were programmes about the past fit only for the past. After Middlemarch, commissioning editors would rather not do a classic at all than do it less than lavishly. “Period drama,” says ITV’s Mackie, “is the most expensive genre to make so we could never do masses of it. It is the cherry on the icing on the cake.”

Yet there are things to be said for the ethos of the cheap and gloomy adaptation. You do not need togamble half your department’s budget to make it. You do not, to ensure ratings, have to choose only the most loved books. Since they cost less, you can make more. “In the 1960s and 1970s,” says Harwood, “the BBC did almost every Eng Lit novel there is. Blimey, I remember Villette – ten half hours in 1978.”

And if, with the honourable exception of Cranford, it is now hard for television to justify adapting the unjustly neglected, the millions it spends on the Alist must mean there is less money available to dramatise contemporary Britain. A producerwho did not want to be named thinks commissioning editors actually prefer their writers dead. Hardy and Gaskell are not going to storm into your office to demand more money or pull out citing creative tensions. Their politics are containable. Maybe this is why you rarely see TV adapting a modern historical novel, such as Susanna Clarke’s Jonathan Strange and Mr Norrell or Iain Pears’s An Instance of the Fingerpost, even though both would offer frock coats and bonnets galore.

It is still, of course, possible to turn a classic into a damp squib. No one bought the BBC’s Wives and Daughterson video; Daniel Deronda did not even make it that far. But you would have to do something pretty terrible not to make money out of Jane Eyre. As it happens, Susanna White’s version last year was a critical and popular triumph. Significantly, however, White is now working neither on a classic nor in British television. She is in South Africa for HBO making Generation Kill, a drama about the US Marines in Iraq.

“They are doing an awful lot of period drama this year,” White sighs of the BBC. “I certainly felt that I wanted to go out and do something contemporary having done Bleak House and Jane Eyre. The big appeal of doing this piece about the Marines is that it is a very modern story.

“Classic novels are a very safe bet. There’s a guaranteed audience and guaranteed DVD sales. But at the same time people are going to watch Life on Mars, too. There ought to be room for both.”

So, when tomorrow we immerse ourselves in Cranford, we should not allow our armchairs to become too cosy. Birth, copulation and death may be contained within Cranford’s market square, but there is also, to quote another author neglected these days by television, a world elsewhere. With all the care and enthusiasm that TV drama currently reserves for the past, we need to be shown it.

— Cranford, Sun, BBC One, 9pm

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