With an all-star cast of favourite British TV faces and its timely plot about debt and greed, Andrew Davies's adaptation of Little Dorrit should have proved ratings gold.
Yet audiences for the lavish adaptation of Charles Dickens's novel, one of the Victorian author's more weighty tomes, have been sliding at a rate to rival the stock exchange since the first episode was broadcast last month.
Now, halfway through the 14-part run, barely four million viewers are regularly tuning in to each episode to catch up with the changing fortunes of William Dorrit (Sir Tom Courtenay) and his daughter Amy, played by newcomer Claire Foy. The first episode gathered a healthy 6.3 million viewers, but last Wednesday's audience was only 3.8 million.
The BBC is renowned for its costume dramas, and enjoyed regular audiences of more than six million viewers for its serialisation of Dickens's Bleak House, starring Gillian Anderson, in 2005. Last year's Cranford, a dramatisation of Elizabeth Gaskell's tales set in a Cheshire town, starring Judi Dench and Eileen Atkins, attracted almost 8.5m viewers, while Thomas Hardy's Tess of the D'Urbervilles last month pulled in 5.9 million viewers.
Critics, who have praised the production and acting in Little Dorrit, suggest the theme of debt may be putting viewers off, and that the story is more slow-moving than that of Bleak House. The novelist Beryl Bainbridge, who earlier this year questioned the BBC's appetite for costume drama, said yesterday that she couldn't get to grips with the latest series. "The scenes are good but I can't believe in it," she said. "When I see Sue Johnston, who is very good, I remember her from Brookside. It's just not real enough... That world has vanished."
Philip Reevell, a TV commentator for Broadcast magazine, said: "Broadcasting in 30-minute instalments worked for Bleak House, [but] if the story doesn't carry it then it has the potential to be quite damaging."
A BBC spokeswoman said the corporation was "very pleased" with how the series is doing: "Audiences have two opportunities to watch Little Dorrit – weekly episodes on Wednesday and Thursday, and the Sunday omnibus." She said that the combined audience for these broadcasts is averaging over seven million viewers, "as we expect for a drama of this type".
Based on: Charles Dickens's 1857 novel about debt, greed and bureaucracy
Stars: Tom Courtenay, Claire Foy, left, and Amanda Redman
Critics said: "Brilliant, obviously"; "Accomplished rather than inspired"; "A witheringly appropriate choice for today"; "Not... as impressive or involving as 'Tess' or 'Bleak House'."
Ratings high: 6.3m
Sex factor: (4) Once again Andrew Davies sees something in the novel that even Dickens missed, and inserts a lesbian tryst between the enigmatic Miss Wade and angry protégée Tattycoram
Based on: Charles Dickens's 1853 satire and thriller about a never-ending legal case
Starred: Gillian Anderson, Charles Dance, Denis Lawson and Burn Gorman (above)
Broadcast: October 2005
Critics said: 10 Emmy and two Golden Globe nominations. Lauded for innovative 30-minute episode format
Ratings high: 7.32m
Sex factor: (1) Screenwriter Andrew Davies decided Dickens didn't understand the sinister side of the relationship between John Jarndyce and his ward, Esther
Tess of the D'Urbervilles
Based on: Thomas Hardy's classic 1891 tragedy of unrequited love and misguided ambition
Starred: Gemma Arterton, above, (most recently 'Quantum of Solace' Bond girl) and Eddie Redmayne
Broadcast: September 2008
Critics said: As grimly languorous and glum as Hardy was
Ratings high: 5.96m
Sex factor: (3) A tale of rape and lust; not much in the way of light relief
North and South
Based on: Elizabeth Gaskell's 1855 social novel, billed as a passionate love story between middle-class Margaret Hale and northern mill owner John Thornton
Starred: Daniela Denby-Ashe and Tim Pigott-Smith, above, and Richard Armitage
Broadcast: November 2004
Critics said: Largely unnoticed because the BBC gave it a low profile, but massively popular with viewers who voted it Best Drama on the BBC's annual website poll
Ratings high: 6.75m
Sex factor: (4) Thornton's brooding persona drew parallels with Jane Austen's Darcy and earned Armitage (now smouldering in BBC drama 'Spooks') a host of female fans
Based on: Three soap opera-esque Elizabeth Gaskell novels set in a small 1840s Cheshire market town
Starred: Michael Gambon, Imelda Staunton, Judi Dench and Eileen Atkins (pictured)
Broadcast: November 2007
Critics said: Nominated for four Bafta TV awards, seven Bafta craft awards and eight Emmys, it proved that Dickens hasn't cornered the market in posh TV adaptations
Ratings high: 8.43m
Sex factor: (2) With gossips, bachelors, spinsters and tragedies, it gave 'Coronation Street' a run for its money
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