Playing nasty has served Glenn Close nicely over the years and as the underhand lawyer Patty Hewes in Damages she's never been more cut-throat. Close won a Golden Globe and an Emmy for the first series of the New York legal thriller on top of the critical acclaim and passionate devotees that the show attracted. Damages, which applies a glossy sheen to its world of skulduggery, violence and sex, returns for a second season on BBC One this month. Nobody knew that a quality television show could be so wildly addictive or suspenseful.

Damages serves up a complex, multilayered narrative, blending present, past and future plotlines to highlight the lies and deceit that engulf its characters. The first series ended in typically ambiguous fashion with Hewes emerging as both hero and villain. She won her class-action lawsuit against the corrupt insider-trading billionaire Arthur Frobisher (Ted Danson), shot at the end of the first series by a disgruntled employee, but she ordered the attempted murder of her protégée Ellen Parsons (Rose Byrne). In revenge Parsons has become an FBI informant, determined to bring down her boss.

Sceptics complained that the first season's flashy storytelling spilt into implausible territory with the multiple murders and mayhem. But the disgraced financier Bernie Madoff is currently public enemy No 1 in New York for his alleged $50 billion pyramid scheme and barely a day goes by without some reference to corporate malfeasance. Right now we could do with a few real-life Patty Heweses taking on the corrupt money-men.

When we meet in a windowless office in the Brooklyn studio where Damages is filmed, Close, 61, is keen to point out that her latest rapacious incarnation is more complex and exudes more vulnerability than she is given credit for. “People come up to me and say: ‘You're so evil',” Close explains, laughing. “I say: ‘I'm not evil', that's a very strong word for a human being.” How does she defend her? “I don't, because that's how she is... the bottom line for her is she hates bullies.”

Why is Close, whose schemers and sociopaths in Fatal Attraction and Dangerous Liaisons disturbed audiences in the late Eighties, continually drawn to dark material? Partly it's typecasting. “You are only as good as the material that you are offered. If I was offered the part of [someone] very weak and I thought it was challenging, I'd be just as up to do that.” People enjoy her behaving badly: “It might be harder for them to perceive me in other roles.”

She's adamant that Hewes is a victim of sexism. “A powerful woman who is manipulative, who gets what she wants - she's immediately an evil bitch,” she says. “If you had a man in this role, I don't think they'd call him an evil bastard.”

The twinkle in her eye that appears every time she discusses Hewes signals that she gets a kick out of the part, but Close is warmer and more sensitive than her character. She didn't dare ask the female lawyers whom she consulted for research what they thought of her finished performance and she claims she was “too scared” to watch any advance footage of Damages before the New York premiere of the second series. “It's kind of shocking how many people have come up to me and said they think [the law firm is] really true to life. I think: ‘Where do you work?'”

Close now finds television a far more rewarding medium than film. “If you're in a play or a two-hour movie you know the beginning, the middle and the end,” she says. “With this, you don't. So it's very insecure at the beginning. But then you just learn to go with the flow. It is like living a novel... we're really making mega-movies.”

Illustrating the clout that quality television now wields, two Oscar-winners, William Hurt and Marcia Gay Harden, appear in the second series. Hurt, who Close last worked with on the 1983 baby-boomer comedy The Big Chill, found the transition from the big screen to a smaller one a painful one. “He was miserable,” Close says. “He was not used to having this short a time to prepare. And then you might have prepared and then go in and have a totally rewritten scene. He found that impossible and difficult.” Hurt says that he adjusted to it but this is his one and only series of Damages.

Hurt plays a scientist, Danny Purcell, who has a secret past with Hewes, and who becomes a whistleblower to expose an energy company's illicit dealings. The creators and executive producers of Damages, the brothers Todd and Glenn Kessler and Daniel Zelman (known as KZK), have turned their attention to environmental malpractice in the second series. Close put KZK in contact with Robert F. Kennedy Jr, the renowned environmentalist and son of Bobby Kennedy, who advised them on a fictional coal spillage in Virginia, a plot twist foreshadowed by an actual coal spillage in Kentucky in December 2007.

Claiming to be obsessed with chronicling powerful people and what motivates them, KZK based Frobisher, who returns in the second season, on the plight of Enron, WorldCom and Martha Stewart. “We want our audience to watch the characters [in Damages] the way we're watching these people out in the world,” says Todd Kessler. “Because we can't figure them out!”

Time will tell whether Damages can tie up its convolutions this time as neatly as it did in the first series. “Other shows had let them [audiences] down,” Todd Kessler says. “They've done serialised storytelling where ends aren't resolved, it's just more possibilities. Lost was one of them... we felt almost a backlash.” They have slightly reduced the episodic complexity in the second season but resisted pressure to make their characters more appealing. “You get these notes [from] executives: ‘The character has to be more likeable',” he laments. “Why does the character have to be more likeable?”

KZK are known for supplying scripts to actors at the eleventh hour, sometimes on the day of shooting. Close loves this approach, but Tate Donovan, who plays Tom Shayes, Hewes's right-hand man, says it was initially disconcerting. “It started off as this real challenge and you are like ‘what the f***'. Now it's a liberating experience.”

Ultimately the long-term success of the show depends on the strength of the Hewes-Parsons dynamic, the manipulative sorcerer and her rebellious apprentice. Byrne, a 29-year-old Australian porcelain beauty, has a lot more to do in this series. “The first season was really hard because she was really an underdeveloped character and the producers and I had a lot of discussions and it wasn't always smooth sailing,” she admits. “It was really great to sink my teeth into [the second series] as an actor. That first season I was really lost, and I don't think I was particularly good either until the last two episodes.”

One poster for the second series of Damages has Byrne embedding her stiletto in Close's neck. But its frenzied depiction of Manhattan is the antithesis of the Manolo Blahnik stomping ground of Sex and the City. During the first series, when the producers couldn't afford to build the office for Frobisher's doomed lawyer Ray Fiske, they filmed his meetings on the street, enhancing the show's urban feel in the process.

Despite critical buzz and passionate enthusiasts, the first series of Damages wasn't a ratings hit on either side of the Atlantic. A third season has already been commissioned and the actors have signed up for six series, but the audience will surely have to increase if the show is to have a long-term future. Is it too edgy and dark ever to have mass ratings appeal? “These days, probably,” Hurt admits. “I'm not putting it past any public to go wide on quality now that we are facing the problems we are facing.”

It's a fascinating argument whether a passionate fan base and rapturous critical response is enough for “mega-movies” such as Damages to override a shortfall in viewers. But Patty Hewes is the last person I'd like to have it with.

The new series of Damages will be coming to BBC One later this month

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