"I first read the book last year and I felt passionately about it," the young actor explains, earnestly. "The one thing I minded more than anything was that the film should be funny to watch. I didn�t want it to be a breast-beatingly serious drama about lesbians, which it�s not. It�s a simple tale about this girl and the fixes she finds herself in. It has a vibrancy and an energy that just blow you away." True to the original novel, Davies� scripts do not fight shy of portraying the whole of Nan�s extraordinary story. And though Stirling knew the book "back to front" and has worked with Davies before � he penned ITV�s modern reworking of Othello in which she played the scandalous Lulu � when she received the scripts she admits that she was still taken aback at their candour.

Stirling turns serious for a moment. "But, listen, you don�t see exactly what�s written in the scripts. I�m not saying that you don�t see anything � you do and, needless to say, it�s all justified and done very carefully � but, as [director] Geoff Sax invariably said in every single scene, �It�s more the art of what isn�t seen�. After all, you don�t want to watch your leading girl through clasped fingers, embarrassed at what she�s doing."

"I found it quite hard, during filming, to separate myself from Nan, simply because she�s like most other young women who are trying to find their own identities," she says. "She�s got a wonderful spirit of trial and error about her � she tries anything and goes anywhere and meets anyone, just to try and discover who she is. She throws herself into things 400 per cent. She�s strong, brave and funny, she�s modest and charming. More than anything, she�s determined to find someone to whom she belongs and somewhere to be at home, and the three episodes take the viewer on the journey of her life."

"Through paintings, I�d gathered a certain amount of information about that period and I knew that the pornography that came out of Victorian England was shocking at that time. I also did a fair amount of research into male impersonators like Vesta Tilley; Kitty�s the first one Nan�s seen but it was a pretty common act."

Unlike her co-star, Keeley Hawes, Stirling couldn�t wait to hit the stage for the drama�s rollicking music hall scenes. "I�d done a certain amount of singing and I knew I had a voice in me," she laughs, "and it turned out to be a belting voice rather than starling-like. But I loved the singing and it�s not like becoming a great opera singer - it�s rather more nudge, nudge, wink, wink!

"Performing in front of the audience was great fun but there was something slightly different about when they were doing close-ups of us and there were only six people in the audience. You take a great big bow and there are six people going, �Yeah, it was alright. Cut!� Tipping The Velvet is about love, and it shouldn�t matter whether it�s two women or a man and a woman. Nan�s so funny that you shouldn�t mind whether she falls in love with a man or a woman, you want her to be happy at the end of it.

"If the lesbian theme makes people tune in, then all the better. I hope by the end of it, they�re carried away by Nan and her story, so it overrides any titillation that they first expected. But there�s definitely titillation there � they won�t be disappointed on that one!" she grins.