Gillian Anderson will take on one of the most controversial roles an actress can play on the stage.

She will star as Nora in Ibsen's A Doll's House, which opens at the Donmar Warehouse Theatre in Covent Garden next spring.

A new version of the drama has been written by Zinnie Harris and will be directed by Kfir Yefet. More than a century after Henrik Ibsen wrote A Doll's House, where Nora famously, walks out on her husband and children, that defiant act still has the capacity to shock.

'How does a woman... how can a woman... abandon her children like that?' Gillian wondered, when we discussed A Doll's House on Wednesday in London.

The actress, who has two children and is pregnant with her third, added: 'To some of us, it just feels absolutely shocking. I couldn't imagine it, and yet it happens all the time for one reason or another.'

And in between preparing for A Doll's House and her new baby, Gillian is waiting for the release, in August, of X Files: I Want To Believe, a big-screen movie in which, after a break of several years, she reprises her role as agent Dana Scully. 'They've all matured, which is such a funny word to use because of course we've matured  -  we're ten years older in X Files, and look it,' she said.

The part of Scully made her a star, but she has more than proved her acting abilities in other work, particularly the film House Of Mirth and her spectacular performance as Lady Dedlock in the award-winning BBC TV serial of Bleak House.

But she likes to return to the stage even though, she says, it terrifies her. 'Every time I put up my hand (to go on stage again), it's the other arm trying to pull my hand down,' she said, laughing. 'It's like: "What do you think you're doing?" But it's so rewarding when I do theatre.'

Certainly not in monetary terms, and not at the Donmar, where she'll be on the Equity union minimum of around £400-£500 a week. 'I still choose to get involved in theatre. It's important enough to me in my life, that I think I'd choose it regardless of whether I could feed my children,' she joked.