Helen Mirren's no-nonsense attitudes may have prevented her from achieving Hollywood stardom, her gender disqualified her from great classical roles, and now her age - 52 - leaves her with relatively few lucrative mainstream parts to play. But this has left her free to portray memorable female characters who test the boundaries of both TV drama and social attitudes Helen Mirren is equally popular with both male and female viewers because she is a strong and feisty woman. But don't you dare try telling her that.

"Two phrases I hate in reference to female characters are `strong' and `feisty'," she says. "They really annoy me. It's the most condescending thing. You say that about a three-year-old. It infantilises women."

It's just these sort of passionate, independent-minded views that draw people to Mirren. The person voted the Sexiest Woman on TV in a recent Radio Times poll (and many males' dream "older woman") is nobody's fool.

"People can identify with the fact that she's no-nonsense," says Emma Burge, Mirren's producer on Painted Lady, her latest ITV vehicle. "She's not prepared to put up with any crap. No one can feel she's a shy wallflower - and both men and women like that." This uncompromising approach has not always endeared her to Hollywood, however. "She's prepared to say absolutely what she sees, and she doesn't pander to people," Burge continues. "LA finds that hard to stomach. Her strength and no-shit attitude are too much for Hollywood."

Not that that seems to bother Mirren. "She is fantastically unconcerned about her image," says Allan Cubitt, the writer of Prime Suspect II and Painted Lady. "She's never trying to protect something. She's prepared to risk an awful lot because she's not insecure about the way she will be judged by the press or the public. She recognises that if you are going to create stimulating characters, then you have to be prepared to be reckless."

In person, Mirren wears her 52 years with serene and enviable ease. She is an alluring mixture of the conventionally glamorous and the unorthodox - her immaculate black two-piece suit and fur stole are undermined by the wacky criss-cross tattoo on her left hand. But all the adulation and awards - her stunning performances in the Prime Suspect cycle won her the Bafta Best Actress gong for three consecutive years - have still not satisfied her. She is forever striving to achieve more.

That's why she is now taking on the very different role of Maggie Sheridan in Painted Lady. ITV's new four-hour drama centres on the reawakening of a hippy singer who lost more years than she can remember to sex, drugs and rock 'n' roll. Mirren calls Maggie "a ballsy flake", before adding, "I know `ballsy' is a funny phrase, but somehow `ovarian' just doesn't have the same zing."

For all that, she reveals in between tiny sips of cappuccino, "I'm not inundated with offers, and I don't read as many good scripts as I'd like to. I'm greedy. My age is a barrier in many ways because there simply aren't the roles out there - especially in the classical canon. There isn't a King Lear for women, or a Henry V, or a Richard III. You reach a level where you can handle that stuff technically and mentally, and it's not there. It would have been great to play Juliet, but sadly I never got a chance. If you're young enough to play Juliet, you're too young to handle it. It's Catch 22. Those sort of roles are so hard for women to find."

Would she then consider, like Fiona Shaw or Kathryn Hunter, taking on one of those titanic Shakespearean male roles? "I quite fancy Richard III. I'd love to have played Hamlet as well. I'm too old now - although it didn't stop Mel Gibson," she laughs.

Nevertheless, Mirren is seen as a standard-bearer, a role model for younger actresses searching for the ability still to play sexy leads when old enough to be a grandmother. "It's embarrassing," she says with characteristically dismissive modesty. "What younger actresses are saying is, `I want to be still working when I'm 50.' That's tough for an actress; continuity is the hardest thing in life. I suspect that's what they're saying, rather than admiring me as an actress."

She does, however, perceive a slight improvement in the number of roles actresses of a certain age are being offered. "It's nothing to do with acting, but with life," she contends. "When women get great roles in life, they start to get great roles in films and TV. Look at Janet Reno, Madeleine Albright, and" - at this point, Mirren hisses - "Mrs Thatcher. Because those images are coming at us in life, they are reflected in acting. It is no coincidence that the character in Prime Suspect is based on a real person, DCI Jackie Malton."

Ah, yes, Prime Suspect, the series credited with showing that women could compete with and actually beat men in the viewing figures game. It demonstrated for the first time that a female lead could triumphantly front a major drama. Lesley Manville, who plays Mirren's half-sister in Painted Lady, comments that, "Prime Suspect made a big difference in the television world. It cut through the idea that making a series about women was risky... It seems that finally people aren't frightened to show women with laughter lines."

Jane Tennison, the tough but tender telly 'tec who had to be twice as good as her male colleagues to prove herself, remains an iconic figure in television drama. Mirren tries to account for Tennison's enduring popularity. "She certainly spoke to a whole generation of successful and economically powerful women," she reflects. "They were a market who'd been ignored. They could buy big Mercedes and expensive mortgages and pensions and were a success in the workplace, but nobody had ever shown what it had been like for them to get there. Prime Suspect showed that. Instead of being a victim, Tennison barrelled her way through - as those women did in real life - without whining or going to tribunals."

Is there any chance that we could ever see Tennison again, chain-smoking and pacing around the incident-room haranguing her (mostly male) colleagues for their stupidity and bone-idleness? "Tennison is alive and well and living in cyberspace," Mirren reveals with a smile. "I don't want to do another series - you have to keep moving - but maybe I'd do a special. I don't want to say never again. Did you see `Prime Cracker' that I did with Robbie Coltrane for Comic Relief? We should do some more of those, but serious this time."

Jane Tennison and Fitz, together on screen at last? Now there's a marriage made in ratings heaven.

`Painted Lady' is tomorrow and Monday on ITV at 9pm