After wooing the audience with her bold and sensuous act in "The Dirty Picture", actress Vidya Balan returns with another intense role of a pregnant woman in her forthcoming film "Kahaani", which releases Friday.

Produced and directed by Sujoy Ghosh, this will be Vidya's fourth woman-centric film after "Ishqiya", "No One Killed Jessica" and "The Dirty Picture". The film also features Bengali actor Parambrata Chattopadhayay and Nawazuddin Siddiqui in prominent roles.

"Kahaani" tells the story of seven-month-pregnant Vidya Bagchi, who flies down to Kolkata in search of her missing husband, all alone in the festive city.

With nothing to rely on than just a fragment from her memories about him, Vidya begins her relentless search for her husband Arnab Bagchi. However, all clues seem to be in vain when everyone tries to convice her that her husband does not exist.

Soon she realises that things are not as they seem. She is determined to unravel the truth about her husband - for herself and her unborn child - even if it puts her life in danger.

The actress made director Ghosh wait for a long time before signing up for the film. Vidya didn't like script at the first reading, but the director kept altering it until she finally agreed to be a part of it. Vidya nows considers herself lucky to be a part of the film.

She has been aggressively promoting the movie - dressed like her character along with a baby bump.

While some actress may find it hard to sport a fake baby bump, Vidya admits she didn't have to struggle too much with it.

"It was not tough at all. During our college life, we all friends used to do all the nautankis and these stand-up items. And my favourite role would always be of a pregnant woman. So the walk and all came to me very naturally," said Vidya.

Music composers Vishal-Shekhar, who are known for creating new-age, peppy music, have gone intense in their compositions for "Kahaani". The duo have even made megastar Amitabh Bachchan sing Rabindra sangeet "Ekla cholo re" for it.

The 69-year-old is all praise for the duo.

"This particular, world famous number 'Ekla Cholo', expounding to all that if no one came to you on your calling, walk alone!! And what a fabulous song has been incorporated by Vishal-Shekhar. Truly awesome and worthy of all award," said Amitabh.

Vidya has become one of the most bankable actresses ever since the success of films like "Ishqiya", "No One Killed Jessica" and most recently "The Dirty Picture".

With the film's trailers making waves, Vidya is likely to continue her winning streak with "Kahaani".