Edinburgh, 1987. A festival screening of the colonial thriller White Mischief is followed by an audience Q&A with the director Michael Radford and stars Greta Scacchi and Joss Ackland. A local compère directs the questions, and the discussion is lively.

Eventually, he points to a woman in the audience who, dourly and directly, addresses Scacchi – then a 27-year-old starlet du jour, boasting an impressive CV and a seemingly exotic mix of Italian heat, Australian candour and English froideur. “When are you going to stop playing the dollybird characters and do something decent instead?” barks the woman, stopping Scacchi in her tracks. The compere says politely “I think we’ll pass on that one.” But the damage is done, and Scacchi is gutted.

“It still stays in my mind, even now,” says Scacchi today, thoughtfully masticating some salade niçoise in a swanky London eatery, while her big soulful eyes glaze in momentary remembrance. She is here to talk about a new TV role, as Jane Austen’s sister Cassandra in the BBC drama Miss Austen Regrets, but right now she’s swirling in the recriminations of a career repeatedly hamstrung by her own ineffable beauty. “Because I knew then that no matter how puritanical my views were about doing quality material, there were always going to be people who’d only see me that way – as a dollybird.”

Of course, the phwooor factor of a dollybird is a precious thing in its heyday, and certainly the Scacchi of Heat and Dust, White Mischief and Presumed Innocent had an erotic screen voltage that overwhelmed all public perceptions. A memorable Spitting Image sketch featured Scacchi auditioning for Richard Attenborough. “Shall I take my clothes off now? Don’t you want to see me naked?

There are going to be nude scenes in this film, aren’t there?” she asks, in typically gross caricature. But clichés can be cruel, and Scacchi never made that transition from an Alist vamp to an older Alist vamp like, say, Sharon Stone (in fact, Scacchi turned down Stone’s career-making part in Basic Instinct – she thought, rightly, that the material was tawdry).

Thus, in Miss Austen Regrets, there seems to be a battle raging between Scacchi and her own image. As the elder, wiser sister to the fiery Jane (Olivia Williams), her Cassandra is a bedraggled bread baker, chicken plucker and general rural dogsbody without a dusting of make-up or a single bonnet change in ten years of screen life.

Scacchi is charitable about the role, and says that she did it to work with Olivia Williams, and because it cast an interesting light on Austen’s real life. She is charitable, too, about her forthcoming role in the new Brideshead Revisited adaptation (she plays Michael Gambon’s mistress), as she is about her role as the London wife of a Muslim police officer caught up in a Menezes-style killing, in Shoot on Sight.

And yet, you sense the frustration she feels with her screen career. On stage she has recently proved her mettle in Terence Hall’s touring adaptation of Terence Rattigan’s anti-love story The Deep Blue Sea.

Again, like Cassandra Austen, she is playing against type as a plain, older woman, but one who is emotionally abused by her younger RAF lover. The role, she says, has been rewarding, and proof that she is a performer of some range.

Scacchi studied at the Bristol Old Vic with classmates including Miranda Richardson and Daniel Day-Lewis (whom she briefly dated). Raised in Italy, England and Australia, she made an impression on film, she says, despite her theatrical training, alternating milestone movies such as White Mischief with arthouse outings. Her dalliances with Hollywood, meanwhile, have often been painful, culminating recently in deleted scenes as George Clooney’s wife in Syriana and a fleeting role as Jodie Foster’s shrink in Flightplan.

“And what did you think?” she asks, of her brief Flightplan appearance. “Did you think, ‘She must be desperate, why would she play such a tiny stupid little part?’ ” I tell her that she was credible, but I sense the question was rhetorical. “And now I’ve no choice,” she says, reaching under the table.

She pulls out a script, title hidden, and rolls her eyes. It’s decent money, and will pay the bills for the next six months, but it’s awful – they want her to play an MI5 villain. She groans. “What do I do? Do I just think, ‘OK, I’m crap. I’m washed up. They only ever rated me for my looks. So now, whenever I can cash in, maybe I should?’ ” Again, I’m guessing this is rhetorical. “But somehow I have a little suspicion that I might be better than that.”

She says that the only thing left for a woman in her forties battling the prejudice of a va-va-voom past is to trade on that past slightly. Like, say, Helen Mirren. “It’s the hint, the suggestion that there’s a boiler deep inside,” she says. “Helen Mirren still uses it, and the association is helpful.”

She adds that her own Hollywood adventure was cut short by a turbulent marriage to the Law & Order star Vincent D’Onofrio. They met on the set of the 1991 romantic melodrama Fires Within, got married, had a daughter, Leila, and divorced two years later.

She now lives in a cottage in Sussex with her husband Carlo Mantegazza, who is the father of her youngest son Matteo, and also her first cousin. “Do you think I want to talk about it?” she asks, stiffening at the mere mention of their relationship. It’s a tough call, but I’m going for rhetorical here, too. “Well, no, I don’t want to talk about it,” she continues, before remembering how the paparazzi blitzed her daughter’s school when the story first broke ten years ago.

The mere process of recollection, however, seems to have blackened her mood. “I thought we were here to talk about Austen!” she snaps, before sinking into a complete, lengthy, and slightly strange silence.

“Do you normally do this when you don’t want to answer a question?”, I ask, eventually, non-rhetorically.

“I think it’s the best way, isn’t it?” she replies.

“Well, I’m finding it difficult.”

“Oooh, sorry,” she says, inexplicably melting. “So, what do you want to write about? What would you like to say about me?”

I say that I quite like the whole . . . “The dollybird thing?” she interrupts, excitedly. “No.” “The cousin thing?!” she asks, tentatively. “No”, I say, “I like the idea of your inner boiler.”

“Oh God,” she groans again, “Why did I say that? Although I think I could turn it on if I needed to – what do you think?”

I say nothing. I know the drill. But for the first time that day I think, phwoooor!

Miss Austen Regrets, Sun, BBC One, 8pm

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