Filmmaker Sujoy Ghosh talks about the importance of Kolkata in 'Kahaani' and how Vidya Balan's success rate will effect his film's fortunes Has The Dirty Picture's success been a game-changer for Kahaani? It definitely ensures me a good opening but I am not sure if it is a game-changer because this film will have to speak for itself. But yes, after Paa, Ishqiya, No One Killed Jessica and now The Dirty Picture, Vidya has created a stamp of quality, which is very good.

Why is Kahaani only your fourth film since Jhankaar Beats in 2003?  Nobody wants to give me money to make a film. That's why I have to write a film, go out, beg for money and then make one. I spent around two years developing Kahaani's story and we shot it in 52 days. It was the most challenging movie I have ever made. It was a movie that only Vidya and I believed in.

Why was it such a challenge? I discussed the basic idea with Vidya. Initially it wasn't working out but we finally cracked it and I wrote the story. Then Aladin flopped and I got many 'Nos'. But I could only make it because she fully supported me. It was a challenge because on paper it had a huge budget. We knew we couldn't make it with a big budget as we could not take a solo Vidya Balan to that level. We had to be practical. So we went to Kolkata, and shot.

You wrote the film with Vidya in mind? Yes, it was first Vidya, then Kahaani. I always wanted to work with her. It is a story about a woman who is pushed into an alien environment where she has to survive, protect her child, look for her husband and find the truth. The film is about the maternal instinct.

What was Vidya Balan's reaction when you told her that she had to be pregnant throughout the film? She is a very brave actress and was quite excited. The story demanded a pregnant protagonist. For an actress, it doesn't matter whether she is playing a glamorous role or a pregnant woman. That's her job. How did she prepare for the role? I left everything to Vidya. I never tell actors how to act. That is what they are supposed to bring to the table. Vidya's sister was pregnant at that point of time, so that helped her with the nuances of pregnancy.

Why have you set the film in Kolkata? In Kahaani, there are two heroines - Vidya and Kolkata. It is a very vibrant city, which really helps in a thriller. I know what even one alley will add to the film. Vidya's first movie was a Bengali film, so she is also close to Kolkata. She knew most of the technicians on the sets of Kahaani.

Most of the shots in the film are in crowded locales. How difficult was it to manage the crowds? It was very difficult. Vidya was my crowd controller. Whenever the crowd got out of hand, we would ask her to talk to them in Bengali. There was no point in going to Kolkata and shooting in a room. Plus, the missing husband is out there in Kolkata, so we had to shoot outside.

Why not take a familiar face to play the husband? This film is a journey of this woman, so the husband doesn't have a lot of footage. Normally, if you take a known actor or a big face, it works against you in such a film.