Shirley Henderson: The rise of little voice

Shirley Henderson's career started in the boxing ring, and she's never ducked an acting challenge since. She tells Ryan Gilbey about the night she took her promiscuous character to the disco

In the darkened corner of a hotel tearoom, Shirley Henderson is perched in a regal armchair with pastries spread out on the table before her. She looks like she's holding court and loving every minute of it. "Have a sticky bun," she urges me, gesturing to the plate - to an apricot crown that's wider than her face, to a plump muffin bigger than her fist.

The 37-year-old actress is as dinky as she appears on screen, but despite her sharp brown eyes and pinched doll-face, there is an unexpected softness about her. In her new film, the Glasgow-set love story Wilbur (Wants to Kill Himself) (see Anthony Quinn's review), she plays the introverted, bird-like Alice, who pecks at conversation as though the words are fattening and she's trying to stay slim.

Henderson is more forthcoming, combing her memory to provide comprehensive answers to the simplest questions. She sees Alice as a desolate character who refuses to play victim despite her superficial resemblance to the winsome martyrs of Lars von Trier's "good heart" trilogy. "I realised she was a daydreamer," she says. "It's probably been a while since she had a proper conversation. Maybe she hasn't brushed her hair for a while. I never brush mine, I just wash it and leave it."

Straight after completing Wilbur in early 2002, Henderson played Moaning Myrtle in Harry Potter and the Chamber of Secrets. "There were a hundred technicians, I was wearing masses of make-up and a ridiculous costume, flying through the air in a harness, reacting to marks on walls, no other actors there. That was a bit strange." Myrtle will return in the fourth instalment, but until then Henderson will scarcely have time to open a school fête. She recently appeared as a gone-to-seed wife in Intermission, and next up is Sally Potter's new film, Yes.

The onslaught of work marks a change from Henderson's post-Trainspotting years, when her part in the film that made Ewan McGregor's career did little to alter the steady but unremarkable flow of her own. (If you want to go back to the video, she's one of the faces that gets spattered with flying excrement over the breakfast table.) She was also once a regular in the BBC drama Hamish Macbeth. "Lovely series," she smiles. "Little bit naughty, little bit clever. There's nothing on telly like that now, is there?".

You will have caught Henderson's best work, however, in the past few years. She played the alcoholic actress Leonora Braham in Mike Leigh's Topsy-Turvy (1999), and has repeatedly collaborated with Michael Winterbottom, who cast her as a raunchy hairdresser in Wonderland (1999), as a prostitute in the snowbound Western The Claim (2000) and as Tony Wilson's wife, easy-going to the point of sleepiness, in 24 Hour Party People (2002).

Only the keen-eyed and well-placed will recall her first big success, at Butlin's in Ayre, circa 1977. There, she won a children's singing competition and was spotted by a promoter in the audience. "They asked if I'd like to sing in a boxing ring," she says, as though it were the most natural thing in the world. I wonder aloud if she means before the fight. "Well, it wasn't during!" In the interval, she would duck under the ropes and sing along to the accompaniment of an accordion, while neighbours from her village of Kincardine in Fife looked on. She imagines an exchange taking place in the crowd: "'What's wee Shirley Henderson doing in a boxing ring?' 'Och, she's going to sing a song.' 'Oh, right.'" She chuckles to herself. "The things we did for entertainment..."

From there, she dabbled in youth theatre, and played the working men's club circuit, trilling through the latest hits by Barbra Streisand or Gladys Knight and the Pips, bringing tears to the eyes of her burly and appreciative audience. Henderson never got too big for her little boots, though. "I liked all the silliness, the dressing-up. But I didn't know what it was about. Life went on. I played out, I did my homework. If someone asked me to sing, I said yes. It was all about enjoyment."

Her goals haven't changed much. She sees acting as an "adventure" and when asked why she was drawn to Winterbottom says excitedly, "You can never let your guard down with Michael. The freedom is gorgeous." We agree that a US critic was mistaken in remarking that her Wonderland character, Debbie, a promiscuous single mother, had a "careless" attitude to parenting. "'Carefree' is better," she decides, with transparent protectiveness.

This lovely part in Winterbottom's best film fulfilled Henderson's need for adventure, and not only because she learnt to cut hair while chain-smoking and talking 10 to the dozen. One night, she was dispatched by her director to a Brixton club wearing clothes that she had bought "in character". She leans forward dramatically, as though imparting scandalous information. "I got a necklace, a skirt and a wee skintight gypsy thing from Bay Trading. All for a tenner. I had to be Debbie for the entire evening. And you know what she's like!" She gives a hearty laugh. "I was never going to do what she did and take someone home. I mean, there are limits. But I was there on the dance floor." I ask if she got chatted up. "Oh, yeah! There were men giving it all this." She doesn't specify what "all this" entailed, but I think we can assume they weren't asking her to press flowers with them.

Since the double-whammy of Wonderland and Topsy-Turvy, mainstream film-makers have expressed an interest in Henderson, though it's yet to be proved that they know what to do with her. She was, for instance, wasted in a throwaway part in Bridget Jones's Diary. I expect she will be our Lili Taylor, our Chloë Sevigny - working in the margins, but prone to catch the eye with something quietly daring.

If you want proof, watch the last scene of Topsy-Turvy, in which Henderson recites her lines from The Mikado in the dressing room before taking to the stage for a rendition of "The Sun Whose Rays are All Ablaze": it makes you understand how she broke hearts in the working men's clubs of Scotland. When she was shooting the scene, she had no inkling that it would provide the film with its melancholy climax. "I had to catch a train after the screening, but Mike asked me to wait until the end. Afterwards, he said: 'Wasn't that worth it?'" She pauses. "I just said: 'Thank you.'" Those words are spoken so tenderly that, quite unexpectedly, she has become Leonora Braham all over again before my eyes.