/> Kangana is getting ready for the biggest challenge of her career. She'll be playing whom she considers the most beautiful woman in the history of Indian cinema.

It's a thought that flatters and terrifies her. Kangana is afraid she may not look beautiful enough on screen.

"I've never thought of myself as beautiful. In fact I've always suffered from the low-est self esteem. Till recently I'd look at my pictures and cringe.

I still have the pictures from my first portfolio I got done in Chandigarh. They remind me of how ugly I can look. And to now play Madhubala in Once Upon A Time In Mumbai. How will I do it?"

Kangana is so petrified at the prospect she has stopped looking into the mirror completely.

Kangana laughs when people tell her playing the traumatized mistress of the underworld don would be a cakewalk for her.

"I'm proud of my so-called territory as an actress. If playing traumatized women is my territory then I'm glad. Because I know I'm good at it."

The challenge in Once Upon A Time... is the physicality. "Madhubala's role is not as tragic as my other roles. It's basically a very tender romance between this really funny don (played by Ajay Devgan) and this female superstar who can't understand his personality.

How will I manage to play the most beautiful woman that Indian cinema has ever seen? My characters have always had a dark and light side. And this one is no exception. But the challenge for me is to look almost ethereally beautiful, like Madhubala. How will I manage that?"

Kangana intends to undergo a complete transformation of look and appearance. She has already started watching DVDs of Madhubala's films very carefully. " I won't copy her. But I want to get into her mind and heartspace."