Image copyright ITV Image caption Rose Williams plays Charlotte Heywood, Sanditon's young heroine

Sex, nudity and slavery are not things one normally associates with the world of Jane Austen's fiction.

Yet an invitation to pen a drama based on the 19th Century author's unfinished novel Sanditon gave screenwriter Andrew Davies a chance to buck convention.

"I aim to please myself when writing these things," says Davies, who admits "sexing it up comes fairly naturally".

"If it's not there, I think 'let's put some in,'" he explains. "I like to write it and I like to watch it."

It was Davies, of course, who had Colin Firth taking an impromptu swim in his 1995 BBC adaptation of Austen's Pride and Prejudice.

Twenty-four years on, the first episode of ITV's Sanditon ups the ante considerably by having three of its male leads take a naked seaside skinny-dip.

Image copyright Getty Images Image caption Davies' other dramas include Bleak House and Mr Selfridge

Another provocative scene sees its naive young heroine Charlotte (Rose Williams) stumble upon a man and a woman performing a furtive sexual act in a forest.

A key player in the story, meanwhile, is one Miss Lambe (Crystal Clarke), a heiress from the West Indies whose mother was a slave.

"It was very much a team job," says Davies. "We just sat around talking and thinking and saying, 'Dare we do that? Yeah!'

"Some period stuff can be quite dour and worthy and this is witty and lustful and lascivious," says cast member Kris Marshall.

"It's a new take which lets people feel the people back then weren't so different," says fellow actor Jack Fox of the "risqué" dramatisation.

Austen had completed 12 chapters of Sanditon - originally titled The Brothers - at the time of her death in 1817.

Image copyright ITV Image caption Anne Reid says it was a refreshing change to play "a lady in charge"

ITV's eight-part drama takes these chapters as a starting point before spiralling off in directions that are all its writers' invention.

"I suspect the purists will hate it but we're in the entertainment business," shrugs the actress Anne Reid, who plays the formidable widow Lady Denham.

"Sanditon is a place where anything goes," says Marshall of the fictional coastal town where the drama is set.

The My Family star plays the businessman Tom Parker, an ambitious entrepreneur determined to make Sanditon "the finest seaside resort on the whole of the south coast".

His ebullient character exudes a confidence and a can-do optimism not a million miles from the upbeat rhetoric used by Boris Johnson this week.

While declining to make specific parallels with the new Prime Minister, Marshall remarks there was "an ebullience in England in the early 19th Century that really did fire the country on".

Image copyright ITV Image caption Marshall's character has big plans for the show's titular resort

"Everything is cyclical, and we were moving into the start of the next cycle," he observes. "Are we at the start of a new cycle now? Who knows."

The aforementioned male skinny-dipping contrasts amusingly with the prim Victorian bathing costume Charlotte dons for her own ocean plunge.

Speaking on Friday after a screening of Sanditon's debut episode, Williams said the sequence marked a welcome move away from traditional drama staples.

"For so long it has been the norm for women to expose their bodies, so the shift is needed," the actress told reporters.

"There's more male nudity these days because female nudity can be a contentious area," admits Davies, whose other adaptations include Les Miserables and War and Peace.

"But maybe, you know, the pendulum might swing back."

Sanditon will screen on ITV in the autumn.

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