The making of Shakuntala Devi’s biopic started with a conversation between her daughter Anupama Banerji and director Anu Menon in a café in London four years ago. It was three years after the death of the math genius, and Anupama was still recovering from the pain of losing her mother, when she had to relive her life all over again.

“We met in 2016, about three years after mummy had passed away, and it was a struggle. The pain was immense, and we were trying to get on with our lives but it wasn’t easy for the family. It wasn’t easy to talk about her life. This was reality, we weren’t trying to portray somebody’s life who was perfect. She had struggled. She came up the hard way and wanted to conquer the world,” Anupama tells us.

Looking at her just as a genius mathematician was just scratching the surface. The film seeks to capture various facets of her personality, from her relationship with her daughter to her progressive views in the ’70s.

“She was larger than life. There was so much to bring in. She had so many varied interests, like she wrote a book on cookery for men specifically. This was in the ’70s, when things were different. She was very, very progressive and all that needed to be brought out. The book on homosexuality was probably the first. It was pioneering. No one had ever written a book like that,” Anupama says.

Though it wasn’t easy for her to talk about her mother’s life, Anupama decided to narrate it like it was, and let director Anu Menon and her co-writer Nayanika translate it on screen the way they wanted to.

“We just told them everything like it was and how it was, you know, and I'm so glad that they were able to capture and actually understand, because it really wasn't a normal scenario. It was very different and they seemed to just understand and were able to bring it out,” she adds.

Vidya Balan was the obvious choice for the role of Shakuntala Devi. Anu Menon says that Anupama and her family isn’t very familiar with Bollywood, but they knew about Vidya.

“The one actress that they really loved and respected was Vidya, she was Anupama’s father’s favourite actress as well. You can see how similar they are in the way they approach life and their energy. I just felt like she was the only one who could capture the essence of Shakuntala Devi,” the director shares.

Maths isn’t a very visually appealing subject. But Shakuntala Devi made it seem interesting, and that is how the makers have tried to capture it on screen.

“We found ways of capturing it cinematically. The idea was to make people experience maths the way she experienced it, how it was joyous for her. We've seen films on Ramanujan and Einstein and how they sit in a room with heads full of equations. She was not like that. She was not angsty about maths. It was like her best friend. We have shown it in such a way that even if you are scared of maths you will understand it,” Anu says.

Watching the film after it was made was an overwhelming experience for Anupama and her family.

Anupama narrates, “After we watched it, for a while, we just didn't say anything. It was amazing. A very real situation that we had described to them was portrayed in the most graceful manner. There was that bit of worry, ‘Oh my God, how's it going to come across?’ But it just came across beautifully. And everything was amazing. We were so happy with the end result. It was really a surreal experience.”

Shakuntala Devi, starring Vidya Balan and Sanya Malhotra, will premiere on Amazon Prime Video on July 31.