First, I think his mother fell ill. And then he fell ill. We were in South Africa, with 55 people in the unit, and we had cancel the shoot and return to India. It became imperative that we had to find another Gandhi.

Many people, including the critics, are pleased with the choice of Darshan Jariwala.

Yes. He is a natural actor. I have known him for over two decades. But when I decided to cast him it was clear that he had to lose over 50 pounds within a few months. We had him live at a nature cure farm in Bangalore and got him to lose weight under medical supervision.

He has given a brilliant performance. And the performance has been enhanced by the fact he is a Gujarati. He knows the culture, background and has the body language required for the character. I thought I could mould him and he, on his part, gave himself to the character.

Many people have said the scenes between Kasturba and her son Harilal, who has become a Muslim, are among the most touching scenes they have seen in films in a long time.

I don't know how many times I have seen the film but every time I see the scenes, I cry too.

What was so moving about it?

It is the scene where Kasturba comes to meet Harilal who has now converted to Islam and is now known as Abdullah Gandhi. In the scene, she is talking to her son and partially to herself. There is tiredness in her face; tiredness of a resigned and helpless mother who has failed to build a bridge between the father and the son. I wanted to bring about certain expressions on Shefali Shah's face. And I became a bit of slave master (chuckles).

And what was that about?

I went on asking for more takes, maybe 20 times. Or, perhaps, 30. By the time I was to okay the shot, she was very tired; she was also a bit edgy and irritated. I needed all those expressions. And she delivered much more than what I wanted.