The star, who has to strip regularly for her acclaimed performance in The Blue Room, said she had an attack of first night jitters half an hour before going on stage.

"I couldn't believe I was doing this! So I thought, `Well, if I fall on my face, I fall on my face'," she said.

Kubrick: Plans to see the show

In an interview with Variety magazine, Kidman said she had been shocked by the reaction to the show: "I thought I was doing a small play in a 250-seat theatre - but now they pack it with standing room.

"I've never worked so hard in my life - six weeks in rehearsal - but it is exhilarating. Of course, it was nerve-wracking. But the great thing about theatre as opposed to movies, is every night you can do something new."

"Physically and mentally, everything was taken out of me leading up to the opening of the play - a lot of stress. But it's now one of the best times for me," she said.

The actress has spent most of the past two years living in the UK with husband Tom Cruise and their two small children while working on the film Eyes Wide Shut with reclusive movie maker Stanley Kubrick.