Janet McTeer: 'In the second minute I go bonkers'

When Janet McTeer gets homesick in New York, she does as many expats do: she reaches for the Downton. "It's fantastic," she says, over boiled eggs and soldiers on the Upper West Side. "I am completely addicted. Did you see that scene when Maggie Smith almost falls out of the chair? I pressed rewind on that so many times. It made me laugh until I peed myself. And that hadn't happened in a very long time."

Like Downton Abbey, McTeer is proving a durable UK export. She is currently scaring up a storm in The Woman in Black, a moody gothic adaptation of the novel by Susan Hill, which serves as a vehicle for Daniel Radcliffe's emergence into a post-Potter world. McTeer plays a grieving mother whom viewers quickly twig is completely deranged. Her approach is game, rompy. She sinks her Rada-honed fangs into the scenery with abandon, but her character is never cartoonish, always sympathetic. "I tried to be extremely real and normal for the first minute," she says, "and then in the second minute I go bonkers."

The Woman in Black is the high-profile, high-grossing, high-camp title in what's shaping up to be a year of McTeer. The high acclaim is Albert Nobbs, for which both she and Glenn Close have earned Oscar nominations for their roles as women who live as men in 19th-century Dublin – in McTeer's case, complete with wife. Though McTeer's gruff-voiced house painter won't fool audiences for long (after about half an hour, a show-stopping flash confirms things), it's a great fit. Aged 50, classically trained McTeer is as limber at this kind of leap as she is at ease with The Woman in Black's nouveau Hammer horror.

"There are some roles that are a no-brainer. You just have a sure, instinctive 'Yes!' I could have looked at Albert Nobbs and been all logical about it. But there just wasn't a choice. You look at it and go: 'Of course!'" Her gut proved right. She's fresh back from yet another awards ceremony in Los Angeles. Well, fresh-ish. "It was a crap flight. I'm too tall. You can't lie down." (She's 6ft 1in.) Generally, though, she's having a blast. "You either dread it [the awards season] or decide it is going to be fun."

McTeer is notably unpretentious uncompany. Born in Newcastle, raised in York, she took a job aged 16 serving coffee in the York theatre. She could meet boys and see shows for free. "I remember thinking: 'Wow. This is where I belong.'" But her relaxed attitude to celebrity also stems from the fact that this is her second bite of the cherry. In 1999, McTeer won a Golden Globe and an Oscar nomination as a strung-out single mother in the Sundance hit Tumbleweeds, a part she landed off the back of the Tony she picked up for a Broadway transfer of The Doll's House.

She had her ride on the Tinseltown roundabout, then hopped off and went back to Blighty for eclectic TV work (Marple, Psychoville), niche cinema (Terry Gilliam's Tideland, Kenneth Branagh's As You Like It) and heavy-duty stage roles such as Mary, Queen of Scots in Schiller's Mary Stuart, a part she reprised on Broadway three years ago, since when she has been a US resident (she is married to a native New Yorker). "I used to feel I wasn't really English until I came here," she smiles. "Now I feel like I am really English."

These days – between the awards dos and press calls – she's shooting the fourth series of TV show Damages; again alongside Close, whose praises she sings. "I have always been drawn to strong and interesting women. People who have navigated that world before you and maintained their integrity and sense of self."

McTeer herself has survived through talent and tenacity. She doesn't like to be pigeon-holed. Her heroines were never her own peers, always older women who continued to work well. "I always imagine myself keeping working along their lines," she says.She clearly has a dream role in mind. "Maybe I will get Maggie Smith's role in the remake of Downton Abbey in 20 years' time."