It’s sort of irresistible to be part of this great leviathan that is Harry Potter,” declares Miranda Richardson, who, like the rest of the film’s participants, seems to be either toeing a party line that would shame the North Korean dictatorship or vaunting the greatest outpouring of communal love since the Swinging Sixties. Actually, Richardson’s enthusiasm is entirely genuine. “The sense is it’s part of history, and for that reason it’s great,” she continues. “As it would have been to be part of The Lord of the Rings. And I like the fact that kids everywhere are clutching a hardback book to their chests and huddling off into corners, getting absorbed in a new world. It’s not all about looking at a screen, using their thumbs.”

When it comes to Hogwarts, Richardson has a bit of “previous”, all the same. In a 2003 Comic Relief spoof, you may remember, she put on the matted mane of Hermione Granger to play opposite the Harry’n’Ron of Dawn French and Jennifer Saunders. Around her neck, on a leather thong, she deliberately wore a piece of Quidditch paraphernalia. “My last line was, ‘Are you looking at my Snitch?’” she recalls. “But they wouldn’t let it go out on the air, and I was very sad about that.” Richardson was relieved that Daniel Radcliffe and Rupert Grint had the good grace not to mention this. “But I was a bit nervous of Emma (Watson),” she adds. “I thought she might say, ‘I’m not like that!’” In the new film, Richardson plays Rita Skeeter, gossip columnist for the Daily Prophet, a character JK Rowling had been trying to introduce from the outset, but couldn’t find room for until book number four. She’s more Dame Edna on the page. “And I thought, ‘Well, then, cast Barry Humphries,’” says Richardson. “‘I’m not gonna do that. I’ll do something else.’” She has turned Skeeter into a garishly power-suited vamp, “Vivienne Westwood revisited, with a slightly bubbly perm”, as she puts it. Skeeter’s gift for insinuation seems uncannily similar to that of the real tabloid gossipmongers who did their best to skewer young Emma Watson as being some- what tired and emotional after the film’s premiere party last Sunday.

Several of their kind were used for inspiration. “But I certainly wouldn’t name any,” Richardson sniggers. “Come on.”

Though only a small role, it marks, for Richardson, a return to her long-term collaborator Mike Newell, who directed the now 47-year-old in her breakthrough performance as the condemned Ruth Ellis in 1985’s Dance with a Stranger. With apparent quirkiness, though in reality serious consideration, Richardson followed up her debut triumph by turning down the Glenn Close role in Fatal Attraction. “I thought it was part of a whole series of events and stories that were demonising women,” she says. “And I thought, ‘It’s so easy. You’ve just played somebody the public term a murderer, and now they want you to do the same again.’” She concedes that her career “could have gone in a very different direction”.

Fortunately for all of us, she instead made the somewhat unlikely jump to play the part of Queen Elizabeth in Blackadder II — one of the best-loved characters on British television and one still recalled every time Cate Blanchett, Helen Mirren or whoever tries on the orange Tudor afro. A career as prolific as it is diverse has followed.

Richardson renewed her acquaintance with Newell on Enchanted April (1992), which saw her hit a rich, award-scooping vein of form with films such as Damage, The Crying Game and Tom & Viv. She has twice been nominated for an Oscar, but it remains the one big award to have eluded her. Some are still mystified as to how Richardson’s portrayal of a blubbing emotional wreck in Damage (said one commentator: “She does breakdowns better than the AA”) was ignored in favour of Marisa Tomei in My Cousin Vinny.

“Well, there are all sorts of stories floating around about that one,” she laughs. “They were very rude about Jack Palance (who presented the award for best supporting actress that year), and how he misread it.” Such are the politics of gong-giving, she is not overly concerned by it all — “I don’t think it matters,” she whispers — and she continues to employ her considerable talents to such demanding tasks as not being distracted by Nicole Kidman’s false nose in The Hours.

Richardson has several new films on the go (“I’m very aggressive at the moment,” she says), including Spinning into Butter, with Sarah Jessica Parker; Provoked, an Anglo-Indian collaboration about a Punjabi woman who kills her abusive husband, starring Aishwarya Rai; and Southland Tales, a near-futuristic film set in LA and featuring, among others, Justin Timberlake. More recently, she turned down a year-long stint in Desperate Housewives (“It snowballed into something that would be so disruptive for me”), preferring projects such as Richard E Grant’s Wah-Wah and a forthcoming new Labour-bashing television drama, Gideon’s Daughter, by Stephen Poliakoff, a director with whom she worked on 2003’s The Lost Prince.

Harry Potter and the Goblet of Fire is a long way from Richardson’s first brush with the world of sorcery and illusion, when, on the occasion of her fifth birthday, little Miranda was forced to go through with her celebrations despite feeling rather ill. “My mother had decided to do the posh party thing, so we got the hotel room on the prom in Southport. I was wandering around in a daze, in a white frock, and people were saying nice things. And we had Uncle Tex the magician and his assistant pulling doves out of pans and doing the ball-with-cloth trick,” she says. “Then it was the cake moment, and I had to blow the candles out. And I just did a big multicoloured yawn all the way down the table... I think everybody went home after that.”

Wizardry will be reprised in another instalment of the American miniseries Merlin. Whether Rita Skeeter will make a film return, as she does in the Harry Potter books, Richardson doesn’t yet know. “Well, they like a bit of novelty in the films,” she muses, “so I’m not convinced they’re gonna ask me back. I don’t know. Watch this space.”

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