How Vidya Balan transformed herself to fierce 'Begum Jaan'

"After the workshop when Vidya entered the set, I saw 'Begum Jaan' who is a fierce, manipulative no-nonsense kind of woman, walking in. There was no trace of Vidya Balan," he told the media. The National award-winning filmmaker said the "Kahani" actress has an immense commitment towards her craft.