While the movie is supposedly set in Simla, and has an undefined time period, the time period is variable, and can be measured in part by the presence of Charlie Chaplin movies, which are being presented in the background. These movies include The Kid (1921) and The Gold Rush (1925), and while we do not know when they were released in India, they give us a general time period, although this might not fully explain the extravagant European setting of the area, even though the British Raj was still in force.
Snow was essential for the story, so for the first part of the shoot, the entire unit went to Simla in mid-January. It was cold but there was no sign of snow. Since the unit could not wait around, kilos of salt bags bought from the local market and snow making machines from Bombay helped complete that schedule. The shooting would be done early at 4 am. And when the locals emerged they'd be amazed to see so much snow; it looked so authentic that they would touch it to check whether it was real. Dogs would come and lick the salt. The day after the unit left Simla, it snowed heavily.
The movie's title was registered with Kumar Gaurav; Sanjay Leela Bhansali approached him and requested him to relinquish the title, as he wanted it for his movies. Kumar felt that the film was bold and path breaking and wanted to render any help that he could to the film. Hence the reason Sanjay expressed his gratitude to Kumar Gaurav in the opening credits.
Unusually for a work by Bhansali, there are no songs featured in this film. So the background score became of paramount importance to the composer, Monty. To create more of an uplifting aura for the deaf-blind-mute character of Michelle McNally, he used pianos and strings, but kept the voices in the chorus at a low octave. For Debraj Sehai's character, a fighting spirit needed to be vocalized, so Monty used a little-known Middle Eastern instrument called a duduk.
The shooting of the movie ran into trouble in Scenic Hill Resort, with authorities refusing to allow shooting in the premises of a heritage building. Indian Institute of Advanced Study (IIAS) refused permission to shoot in the 120-year-old building as the arc lights could affect the vice regal lodge heritage structure. The building was home to British viceroys from 1886 until 1947, after which it became the summer home of the president of India and since 30 years houses the IIAS.
Director Bhansali hoped to make a film that was an extension of his critically acclaimed (box office flop) debut film Khamoshi: The Musical (1996). Both were based on a visit he made to the Helen Keller Institute.
Zamir Dhale a deaf-blind, proficient in tactile signing language. He stayed in Shimla during the time of the shooting to help Amitabh Bachchan and Rani Mukherjee understand the world of the blind and the deaf.
During a award function child Ayesha Kapur received an award for the film and started calling Amitabh Bachchan by his name frequently as Amitabh.This did not go well with many as Amitabh Bachchan is the biggest star of Hindi cinema and is given a lot of respect.Rani Mukherjee who won Filmfare best actress award referred him as Amitabh uncle with respect.
Sanjay Leela Bhansali got the idea of making the film during his debut film Khamoshi 1995.He was inspired by Helen Keller's autobiography The Story of My Life and visited the Helen Keller Institute to do research.